A new flora of Northumberland and Durham with sketches of its climate and physical geography/Part 1
NATURAL HISTORY
TRANSACTIONS
OF
NORTHUMBERLAND AND DURHAM.
A NEW FLORA
OF
NORTHUMBERLAND AND DURHAM,
PART I.
GEOLOGY, CLIMATOLOGY, AND PHYSICAL GEOGRAPHY.
CHAPTER I.
GEOLOGY, BY GEORGE TATE, F.G.S., &c.
The two counties have an area of 2905 square miles. The surface of the district rises from the sea coast to the westward, as far as the elevated ranges, forming the backbone of England, and the dividing ridge between the eastern and western coasts; and hence all the rivers and streams flow eastward into the German ocean. The western boundary, on the northern part of Northumberland, is formed by the porphyritic range of the Cheviots, the highest elevation being 2676 feet; and further southward by sandstone hills and ridges from 500 feet to 1809 feet in height. Southward of the Tyne, the whole slopes away from the Penine range, whose culminating point, Cross Fell, 2901 feet above the sea level, is but a short distance beyond the district. The physical aspect is therefore very varied : along the coast are some broad plains ; further inland are low rolling hills, and then long broad high ridges, expanding into dreary moorlands; but on the western borders there are, in some parts, fine conical smooth hills, and in others high rugged cliffs. A few wide valleys there are through which larger rivers flow ; but the burns and waters wend their way from the hills through contracted vales and narrow picturesque denes. This inequality of surface is of itself favourable to the production of a varied Flora; and these conditions have been made more favourable still by the variety of the rock formations ; for not only are there series of strata, differing in mineral character and disintegrating capability, from the old Greywacke up to the New Eed Sandstone, but also a number of igneous rocks in mountain ranges, in overlying masses, and in lateral and vertical dikes. In describing the geology of this district I shall begin with the oldest sedimentary strata, and follow the succession of formations up to recent deposits, and then notice the various igneous rocks. The whole are arranged in the following table: —
| AQUEOUS ROCKS. | ||
| PALAEOZOIC ERA. | ||
| I. | Cambro-Silurian System. | |
| II. | Upper Old Red Sandstone Formation. | |
| III. | Carboniferous System, in four Formations. | |
| 1. Tuedian. | ||
| 2. Mountain Limestone in two groups. | ||
| a. Carbonaceous. | ||
| b. Calcareous. | ||
| 3. Millstone Grit. | ||
| 4. Coal Measures. | ||
| IV. | Permian System. | |
| Magnesian Limestone Formation. | ||
| MESOZOIC ERA. | ||
| V. | Triassic or New Red Sandstone. | |
| CAINOZOIC ERA. | ||
| VI. | Plistocene. | |
| Boulder Clay, Gravels, Sand. | ||
| VII. | Post plistocene. | |
| Gravels, Peat. | ||
| IGNEOUS ROCKS. | ||
| Feispathic. | ||
| Porphyry, Syenite. | ||
| Augitic. | ||
| Basalt, Greenstone. | ||
I. CAMBRO-SILURIAN.
Cambro-Silurian strata occupy but a small area in the western part of Northumberland, and do not occur in Durham. They are highly inclined against the porphyry, in the bed of the Coquet a little above Philip, and extend beyond the source of that river into Scotland. In a deep ravine, eastward of Makendon, they are well exposed ; and the Roman camp at Chew Green is formed out of them ; for some of the rampiers are natural walls of Greywacke in situ, the rock having been removed on both sides. Southward of the Coquet they extend for some distance along Watling Street. They appear, too, in the bed of the Reed, near to Ramshope, and up the River beyond White Lee, and up the Carter Fell, by the road side, nearly as far as the toll bar. They are a prolongation into Northumberland of the same formation, which runs across Berwickshire, from Siccar Point in a west south-west direction, and which occupies about one-third of Roxburghshire, with rolling hills of moderate elevation. In Northumberland these rocks reach a height of 1700 feet above the sea level, and consist of distinctly stratified Greywacke and Greywacke Slate; but though much jointed, and divided sometimes into flat irregular prisms, they have no slaty cleavage. Crushed and squeezed, highly inclined, and folding over each other, their dip is irregular both as to direction and amount, yet the general strike of the beds is, on the Coquet, from north-west to south-east, and on the Reed from west to east. Composed of felspar and quartz, with a little mica and sometimes chlorite, their disintegration yields a soil retentive of moisture; but as drainage is effected through numerous joints and the highly inclined planes of stratification, the soil above them is comparatively dry. The protusion amongst them of mighty masses of igneous felspathic rocks, in the border counties, seems to me sufficient to account for their elevated and crushed condition.
Their position in the geologic series is thus far certain—they are much older than the Old Red Sandstone conglomerates, which cover them unconformably in Berwickshire and Roxburghshire; and on the Reed they are in like manner overlaid by Mountain Limestone beds. Fossils have not been detected in them in Northumberland, nor in Roxburghshire; but Mr. Stevenson, of Dunse, has found a Graptolite and tracks of an annelid in Greywacke, on the Dye Water, in the northern part of Berwickshire, in beds, however, which appear to be high in the system. The Northumberland strata may be of the same age as the Longmynd rocks, referred by Sedgwick to the Cambrian, and by Murchison to the Lower Silurian system; and hence, until more definite knowledge is obtained, they may conveniently be designated Cambro-Silurian.
II. UPPER OLD RED SANDSTONE.
Red Sandstone conglomerates, of considerable thickness, but occupying an inconsiderable area, appear on the flanks of the Cheviots at Roddam and Biddlestone, in Northumberland, at elevations from 500 to 700 feet above the sea level. In the deep, narrow dene of Roddam, they are exposed for upwards of a mile, consisting principally of conglomerates formed of rounded pebbles of Cheviot porphyry, from the size of a pea to that of the human head, scattered through a flesh and brick-red clay and sand, loosely bound together by peroxide of iron. Interstratified with these are thin beds of harder conglomerate with smaller pebbles, and thin beds of greenish chloritic, calciferous sandstones, some of which contain as much as forty per cent, of carbonate of lime. Above the loose conglomerates are soft thin bedded red sandstones, and below them are hard red sandstones, with large ripple marks. These beds are not less than 500 feet thick. Organic remains I have not found in them; but as their mineral characters and geological position correspond with the Old Red conglomerates of Berwickshire and Roxburghshire, they may, without much doubt, be grouped with this formation. In Biddlestone Burn they are close upon the porphyry of the Cheviots, and they are overlaid conformably by Tuedian strata.
The red conglomerates of the border counties are more connected with the Carboniferous, than with the Devonian system. In some parts of Scotland there is a physical break between them and the Lower Old Red Sandstone. Their relations are best seen in the section from Siccar Point to the northern extremity of Berwickshire, where they distinctly rest on the upturned edges of the Greywacke or Cambro-Silurian strata, and are conformably overlaid by beds of the Tuedian age, the line between the two being marked by the occurrence of Holoptychius nobilissimus in the red conglomerate, and of Stigmaria ficoides in the Tuedian beds. In this Upper Old Red Sandstone one determinable plant, Adianthoides Hibernicus, has been found in Berwickshire; and from similar beds in Roxburghshire I have seen casts of pretty large stems, probably belonging to Sigillaria. A dry fertile soil is produced by the disintegration of these rocks. 
III. CARBONIFEROUS SYSTEM.
The Carboniferous system occupies fully three-fourths of the district, and has a thickness of about 7000 feet. It is divisible into four distinct formations, all of which are conformable to each other, and marked by the occurrence of Stigmaria ficoides.
1. Tuedian group or formation I applied, in 1856, to a series of beds, intermediate between the Mountain Limestone and the Upper Old Red Sandstone, having an aggregate thickness of about 1000 feet, and consisting of grey, greenish, and lilac shales, thin beds of argillaceous and cherty limestones, a few buff magnesian limestones, and of sandstones and slaty sandstones, several of which are red, and some, near the bottom of the series, of considerable thickness. Several, too, of the shales and sandstones are calcareous; so that, though the limestones are thin and impure, there is a considerable quantity of calcareous matter diffused throughout the formation. The limestones are too impure to burn into lime, excepting a curious bed of magnesian limestone, near Carham, which is composed of carbonate of magnesia 44, carbonate of lime 49.6, silica 4, and peroxide of iron 1.2, alumina 1; and in this are nodules of red and grey chert, analogous to flints in chalk. Stigmaria ficoides, Lepidodendra, coniferous trees, reed-like stems on which are Spirorbis, a Sphenopteris, and other carboniferous plants, occur both in the sandstones and shales; but there are no beds of coal. The Fauna generally consists of Rhizodus Hibberti, Gyracanthus, and other fish; and of mollusks allied to Modiola. Fresh-water or lacustrine conditions are generally indicated; for few distinct marine organisms appear, and where discovered were accompanied by plants in a fragmentary condition, which seem to have been swept into a shallow estuary. One bed of shale, with irregular layers of impure limestone, contains broken trunks of Pinus primaeva and antiqua, showing internal structure, and associated with Orthoceras multiseptum (n.s.), Murchisonia Verneuliana, Pleurotomaria, and a few other marine forms. Brachiopods and Encrinites, which are so abundant in the Mountain Limestone, are almost entirely absent; I have seen only a few crushed specimens of a Rhynchonella in a shale bed at Garmitage Bank. This formation occupies a considerable area in the Merse of Berwickshire; and it is well developed in the Valley of the Tweed from near the mouth of the Whitadder to Makerston, and hence the name Tuedian has been given. It appears in the Vale of Till, and on the flanks of the Cheviots. In Akeld Burn, about 100 feet of characteristic beds are tilted up against the porphyry at an angle of 85°. It is seen also in Biddlestone Burn, in the Coquet below Linn Brig, and on the Bidlees Burn. At Linn Brig, where these beds are in direct junction with the porphyry, they are highly elevated, disturbed, and shattered. A section of them is in Crawley Dene, near to Glanton; and by a great fault they have been thrown up on Garmitage Bank, 5 miles westward of Alnwick. Their relation to other formations is best seen on the Berwickshire coast, where they are intercalated conformably between the Upper Old Sandstone and the Mountain Limestone.
2. The Mountain Limestone occupies above two-fifths of the district; but it is principally spread over Northumberland northward of the Tyne. It comes out beneath the Millstone Grit in the valleys and hill sides of the South Tyne, of the East and West Allen, of the Derwent, of the Wear, and of the Tees; but, as these portions are cut off by the Stublick Dike from the northern beds, and are moreover of a somewhat different type from them, it is necessary to notice each series separately.
Northward of the Tyne the Mountain Limestone consists principally of sandstones and shales, with beds of limestone and coal interstratified, and of ironstone nodules and layers among the shales. The general direction of the strata is south-westward, with a rise towards the north-west; but in their range they are interrupted by many faults, which however have the effect of extending the same beds from the Tweed to the Tyne. They are prolonged in a narrow band along the Berwickshire coast as far as Lammerton Sheal. A line from the mouth of the Aln to the Tyne, a little east of Corbridge, nearly marks their eastern boundary. The area occupied by them in the North is narrowed by the intrusion of the porphyry of the Cheviots; but, southward of that mountain range, they spread out and extend to the western border of the county. Sections may be seen in the affluents of North Tyne, in the Irthing, in the sources of the Reed, in burns flowing into the Aln; but more complete series appear along the coast from Alnmouth to Lammerton Sheal; and these, with the pit sections of Lowick, Scremerston, Sunderland, Eglingham, Shilbottle, &c., give pretty full information of the thickness, the succession, and the organic contents of the several beds. From such data I estimate the total thickness at 2600 feet. The predominant rock is sandstone, of which there are about 1400 feet; of shales there are 900 feet; of limestones 230 feet; and of coal about 70 feet. The sandstones are generally free gritstones made up of grains of quartz and felspar, with a little mica; and when in solid beds forming durable building stones. The shales are mud beds, in which alumina predominates, forming, when disintegrated, a tough clay sub-soil, several of which are loaded with carbonaceous matter; but there is no hard line between a sandstone and a shale, for slaty sandstones, by a larger admixture of argillaceous matter, become a kind of shale; and even some shales are so carbonaceous as to be combustible. The limestones are mostly tolerably pure carbonate of lime; but some beds become magnesian, especially when near to basaltic dikes. The limestones alone, however, do not give us the full measure of carbonate of lime distributed throughout this formation, for many of the shales are highly calcareous, and abound in marine organisms: one such bed at Howick is 15 feet in thickness.
The name, Mountain Limestone, is not physically descriptive of the Northumbrian series, for they contain no thick beds of limestone — none exceeding 30 feet; they form no great cliffs, nor rise to high elevations. In the Lowick district, where most of them crop out, they ascend to a height of only 300 or 400 feet above the sea level; some of the lower beds are seen, on the higher moorlands, at an elevation of 600 feet; and one bed appears, above the Plashets Coal, in North Tynedale, at a height of nearly 1000 feet. But even in these loftier positions they have no influence on the features of the country, which are determined by the thick dominating sandstones, which crest and form the bulk of all the loftier hills, and, along with the associated shales, give character to the high bleak moorlands ranging through the centre of Northumberland, and spreading towards the south-western borders of the county.
These Mountain Limestone strata may be separated into two groups, both having certain organic forms in common, yet each marked by differences, partly organic, and partly mineral. The upper group, which may be designated calcareous, includes all the beds, from the base of the Millstone Grit, down to the base of the Dun Limestone, the lowest limestone of any value in the formation: it has an aggregate thickness of about 1700 feet, and is chiefly distinguishable by its good workable limestones, interstratified among alternations of sandstone, shale, and coal, and by the large number of marine organisms connected with the calcareous strata. Of limestones there are upwards of twenty different beds from 1 to 30 feet thick, and having an aggregate thickness of more than 200 feet. A little below each limestone is a coal seam, or traces of coal. Some seams are of fair quality, two, the Shilbottle and the Licker coals, are of superior quality, and one, the Beadnell coal, is in some parts 5 feet thick; yet most of the others are poor and thin. This calcareous group is on the same zoological horizon as the Lower or Scar Limestone of Yorkshire, for it yields such organic forms as the following, most of which occur in the Mountain Limestone of Ireland, and many of them in strata of the same age in Fifeshire and elsewhere in Scotland.
Aulopora gigas; Chætetes septosus; Hydnopora cyclostoma; Favosites parasitica; Stenopora tumida; Lithodendron affine, junceum; Lithostrotion striatum, Portlocki; Syringopora ramulosa; Archæeoidaris glabrispina, Urii; Cribellites carbonaria; Serpulites carbonarius, Sabella antiqua: Griffithides Farnensis, the only species of a trilobite I have found; Glauconome pluma, pulcherrima; Athyris ambigua, hastata, plano-sulcata; Chonetes Hardrensis, Dalmaniana, polita; Orthis resupinata; Spirifer striatus, trigonalis, glaber; Spiriferina laminosa, octoplicata; Rhynchonella pleurodon; Streptorhynchus crenistria; Productus Cora, fimbriatus, longispinus, spinulosus, Martini; Lingula squamiformis; Aviculopecten concentrico-striatus, tus, coelatus, cancellatus, docens, duplicostata, varii-ornatus, conoides, interstrialis; Amusium Sowerbyii, deornatum; Pecten subelongatus; Pinna flexicostata, flabelliformis, membranacea; Pteronites angustatus, persulcatus; Posidonia Becheri; Streblopteria pulchella; Myalina Verneulii; Lithodomus dactyloides; Area cancellata; Bysso-arca costellata; Nucula gibbosa; Leda attenuata; Solemya primaeva; Leptodomus costellatus; Schizodus axiniformis, carbonarius, deltoides; Conocardium elongatum; Edmondia sulcata, unioniformis, arcuata ; Cardiomorpha oblonga, striata; Sanguinolites sulcatus, variabilis, iridoines; Conularia quadrisulcata ; Dentalium dentaloideum, priscum ; Capulus trilobus ; Pleurotomaria atomaria, sulcatula, decipiens, angulata, helicinoides; Euomphalus carbonarius, acutus, catillus, Dionysii; Macrocheilus acutus, Michotianus, limnaeformis; Naticopsis plicistria; Loxonema rugifera, sulculosa, elongata; Platyschisma helicoides; Bellerophon Urii, decussatus, striatus, hiulcus, apertus; Nautilus ingens, globatus, perplanatus, sulcatus, subsulcatus, costata-coranatus; Goniatites sphaericus; Actinoceras giganteum; Orthoceras sulcatum, Gesneri, inequiseptum, attenuatum, fusiforme, cornu-vaccinum, &c.
The Lower or Carbonaceous group, from the base of the Dun Limestone to the top of the Tuedian formation, has a thickness of about 900 feet, and is especially marked by the number, thickness, and quality of its coal seams. In this we have in descending order the following eight seams of workable coal, viz., the Fawcet or Falcet Coal, about 40 feet below the Dun Limestone, is from 18 inches to 3 feet 4 inches thick; the Scremerston Main Coal is from 2 feet to 4 feet; the Stoney Coal from 1 foot to 3 feet 6 inches, but of poor quality; the Main or Cancer Coal from 2 feet to 7 feet; the Three-quarter Coal, of inferior quality, from 2 feet to 4 feet; the Cooper or Cowper Eye Coal, one of the best for domestic use, from 17 inches to 3 feet; and the Wester Coal from 3 feet to 4 feet 6 inches in thickness. There are a few limestones in this division, but they are thin and generally impure, and their aggregate thickness is only about 20 feet. Some of the marine organisms of the calcareous group appear here, but in fewer numbers. In some shale beds remains of ganoid fish are abundant, accompanied by Schizodus carbonarius, Anthrocomya, Aviculo-pecten, Lingula squamiformis, organisms generally associated with coal seams. This group is intermediate in its characters between the calcareous group of the Mountain Limestone and the Coal Measures; and taking the mass, it is more allied to the latter than to the former. Some thick sandstones near the bottom of the group are red, and might, if colour were a test, be mistaken for Old Red Sandstone.
The Mountain Limestone, southward of the Stublick Dike, differs in some important characters from the northern series: the limestones are very much thicker and greater in the aggregate. Taking the whole series as developed in the district, and in the bordering counties, we find, from Forster's sections, a total thickness of 2080 feet, of which 470 feet are calcareous in nineteen beds, 820 feet are siliceous, and 790 feet are argillaceous. Along the Penine chain, the hills, formed chiefly of such strata, are high, massive, and rounded, with a gradual slope eastward, and a steep inclination to the west, the general dip of the beds being eastward and south-eastward. Here the name is descriptive of the formation; for the thick beds of limestone appear in great cliffs and rise to high elevations, one bed on Mickle Fell reaching a height of 2540 feet above the sea level. The whole, however, is not seen within our district; eleven only of the limestones have been observed, from the uppermost, the Fell Top, to the Tyne bottom Limestone, which, in the neighbourhood of Alston, overlies the Great Whin Sill. We have, therefore, southward of the Stublick Dike, only 900 feet of Mountain Limestone strata, of which 412 feet are argillaceous, 314 feet siliceous, 180 feet calcareous, with only about 4 feet of workable coal. The limestones come to the surface chiefly in the dales, while the siliceous and argillaceous strata occupy the higher grounds; and hence, excepting in these sheltered valleys, or where the limestone spreads over the surface, there is a wide extent of peaty moors covered with heath; and this effect is due also to the predominance of sandstones and shales in the upper part of the series, for of these there are 330 feet between the Fell Top Limestone and the Little or Second Limestone, the intervening strata being similar to those of the overlying Millstone Grit, with which it has been usual to group them.
The limestones are the most regular and characteristic strata. The Fell Top limestone, which is from 2 to 6 feet thick, appears in the dales of the Derwent, the Allen, and the Wear, coming out from beneath the Millstone Grit; it caps some hills near Allenheads, and forms the summit of Middle Fell in Cumberland: it is fossiliferous, and I have found in it Productus semi-reticulatus, Spirifer lineatus, Strophomena rhomloidalis, Orthis Michelini. The third, the Great Limestone, from 54 to 66 feet in thickness, is the most important of all, being more productive of lead than all the other strata united; it forms the bed of the Aleburn for some distance, and climbs the mountain brow of Ale Fell; it bassets out on the north bank of the Tees and near Frosterley, and dips below the bed of the Wear. Its effect on the soil is conspicuous, and has been well described by Mr. Sopwith. "Its basset," he says, "forms, in many instances, the limit of cultivated land and of human habitations. Below it the hill sides, in spring and autumn, present a beautiful green surface, and in summer an abundant and flowery produce in the meadows; while on the same hill, above the limestone, bare short grass, ling, and moss, impart the brown dreary aspect which characterizes all the higher portion of the mining district, rendered in moist weather or in winter still more dreary by hanging mists on the summits, or wasting snows scattered over the wide expansive sides of the hills, but from the massive character of the scenery, rendered beautiful and even sublime by the blue shades of evening, or the subdued effect of moonlight." [1] The Scar Limestone, which has a thickness of about 54 feet, appears in Weardale and Teesdale: for some distance it is the roof of the level into the mine at Alston, and it forms a romantic waterfall at Nent Force. The Cockle Shell Limestone, a thin bed of only 2 feet, abounds in fossils, among which is Productus giganteus, a form distributed throughout the whole formation. Over the Tyne bottom Limestone, which is 24 feet thick, and the lowest in this district, the river runs from the Tyne head for 4 miles; and this bed, along with the strata above it, extend southward over the banks of the Tees into Westmorland. The limestones below this, among which is that of Melmerby Scar, crop out, beyond our district, in Cumberland and Westmorland.
With our present materials we cannot correlate the Mountain Limestone southward of the Stublick Dike with the northern beds in Northumberland, as the physical characters of the two series are so different, and because, moreover, the organic contents of the southern beds are imperfectly known. In addition to the fossils already noticed I have seen the following, from limestone and shale, at Stanhope: Terebratula hastata; Rhynchonella pleurodon; Athyris ambigua; Spirifer integricostatus, octoplicatus, glaber; Pleurotomaria altavitta; Bellerophon striatus; Dentalium priscum. The beds, in this part of our district, have, however, been divided into two groups; those above the Whin Sill, from the Tyne bottom to the Fell Top Limestone, have been referred to the Yoredale series of Philips, and those below the Sill to the Scar Limestone of that author; but this division seems arbitrary, and is not yet supported by organic remains; and it would moreover apply to a limited area only. It would not apply to the northern series; for the Whin Sill, though intruded into the calcareous division of that group, and generally among the higher beds, has no definite place among them—indeed, it cuts through them, and we find its relative vertical position among the strata varying to the extent of 1000 feet.
Throughout the whole of the Mountain Limestone fossil plants, identical with those found in the Newcastle Coal Measures, or analogous to them, occur in the sandstones and shales, and even in the coal itself. The following species are a few of those which have been noticed: Araucarites carbonarius; Stigmaria ficoides, very abundantly; Sigillaria organa, Lepidodendron Harcourtii, obovatum, aculeatum, Sternbergii, selaginoides, gracile, anglicum, &c.; Ulodendron ornatissimum; Knorria imbricata; taxina; Catamites Suckowii, cannaeformis. &c. Perns, so abundant in the Coal Measures, are rare in this group ; in a few localities Sphenopteris Johnstoniana has been found, a species allied to S. gracilis.
Of our modern Flora a few plants in Northumberland are peculiar to the limestone, such as Sesleria caerulea, Potentilla verna, Spiraea filipendula, and Saxifraga tridactylites. A few others, though not entirely confined to limestone soils, rarely grow elsewhere, such as Scabiosa columbaria, Viola hirta, Plantago media.3. The Millstone Grit, which underlies the Mountain Limestone, can scarcely be ranked as a distinct formation, for it differs but little from the Coal Measures, excepting in its feeble development of coal. It is composed of sandstones and shales similar to those in the Coal Measures, and like them, too, it has no limestones or calcareous beds, and but few and doubtful indications of any marine conditions. In this group we include all the beds, from the top of the highest limestone, with marine fossils, to the base of the Brockwell Coal, the lowest workable seam in the Coal Measures. The thickness in Northumberland is about 500 feet; and this corresponds pretty nearly with Forster's section of the formation southward of the Stublick Dike. The characteristic beds are thick gritty sandstones, which sometimes have supplied millstones, and hence the name Millstone Grit. Such beds are made up chiefly of rounded pebbles of quartz and felspar bound together by a siliceous cement : some pebbles in the rock are as large nuts, and some few an inch in diameter. At Warkworth this rock, in some parts, is bound by a calcareous cement, and here and there appear grains of protoxide of iron and garnets. In borings made at Shortridge, two coal seams, each 6 inches thick, were passed through. The proportion of siliceous rocks to the argillaceous in this group is about six to four. Sigillaria, Stigmaria, Favularia, and other Carboniferous plants, occur in the sandstones; and at Berling Carr there are tracks and casts of annelids in slaty sandstones.
These beds in Northumberland range south-south westwards in a narrow zone, from 2 to about 5 miles wide, in the same direction as the Mountain Limestone, on which they rest conformably, from near the mouth of the Aln to the Tyne; but beyond the Tyne they are, through the influence of the Stublick Dike, deflected westward, parallel with that dike, to the borders of the county. Some of the high fell lands of Northumberland south of the Stublick Dike and of the western parts of Durham, are capped by Millstone Grit. North of the Tyne it reaches an altitude of only 460 feet ; but in this southern district the Grey Millstone appears on the- mountains between Wolsingham and Stanhope. The Grindstone Sill, another characteristic bed, is the highest stratum of Allenheads; and beds of this group appear on Kilhope Law at an elevation of 2206 feet, and on the top of Cross Fell, which is 2901 feet above the sea-level.
4. The Coal Measures which overlie the Millstone Grit, occupy, in Northumberland, the triangular area having the Tyne as a base line 14 miles in length; its eastern side is the coast, from the mouth of the Coquet to Tynemouth, and its western side a wavy line from the Coquet mouth to near Wylam on the Tyne. From this base line they extend into the central portion of the county of Durham; and by a fault called the Stublick Dike they are prolonged, in a narrow band up the valley of the Tyne to the extremity of the county of Northumberland, and into Cumberland, a distance of 27 miles. The whole length of this coal field is about 55 miles, having an area of about 700 square miles, marked by undulating ground of moderate elevation rising gently to the west: the highest hills northward of the Tyne are nearly 400 feet, but some in Durham attain to 740 feet above the sea-level.
In these Coal Measures there is almost a repetition of the same characters we find in the Carbonaceous group of the Mountain Limestone, with this exception, that while there were marine relics and a few thin limestones in the earlier period, limestones are altogether absent from the Coal Measures, and there are scarcely any indications of marine conditions. The sandstones, shales, and ironstones are similar in both; but in the more recent period the coals are thicker, richer, and more bituminous. From the variable thickness of the coal-seams in different parts of the field, and from some seams being split into two by the intervention of shales, of greater or less thickness, it is difficult to correlate the seams in distant parts of the field. There appear, however, to be in all fifty-seven seams, having an aggregate thickness of about 80 feet; but as several are thin, only twelve are workable, yielding about 50 feet of good coal. The Three-quarter Coal, which is of poor quality, crops out in the Ouseburn; the High Main, one of the best for domestic use, is 6½ feet thick, and crops out on the declivity of the hill leading to Denton Burn; other good coals, such as the Bensham, Beaumont, and Brockley, are worked in collieries west of Newcastle. Several seams are now worked in the neighbourhood of Sunderland, where the overlying Magnesian Limestone has been pierced to reach the Carboniferous beds: one pit there is 1800 feet deep.
Though some of the posts or sandstones are thick, one being 84 feet, yet the proportion of shales is greater in the Coal Measures than in the Mountain Limestone. Assuming the total thickness of these measures to be 2000 feet, then we have 80 feet of coal, 960 feet of sandstone, and 960 feet of shale; and from this large amount of argillaceous matter, the soil of the Coal Measures is more moist and clayey than that over either the Millstone Grit or the Mountain Limestone, and the scenery, too, is of a tamer character, with fewer bold cliffs and high hills. The low portions of the undulating ground are mostly valleys of denudation; for where the thick argillaceous strata have cropped out the soft material has been swept away, and the surface hollowed by denuding agencies, leaving the harder sandstones as low rounded hills.
No undoubted marine organisms appear in these Coal Measures, excepting one Brachiopod (Lingula mytiloides), which was found by Mr. Kirkby in a bed of shale, at Ryhope colliery, 680 feet below the Magnesian Limestone; but this genus seems to have had the capacity of living in brackish water, probably in an estuary, for we find it also in the Mountain Limestone associated with coal seams, along with Anthrocosia and fish remains. Of fishes several species have been found in different zones, such as {{taxon|Gyracantlius formosus and tubereulatus, Megalichys Hibberti, Diplodus gibbosus, Ctenoptychius pectinatus and dentieulatus, and species of Palceoniscus, Platysomus, Ithizodvs, Aniblypterus, Orthacanthus, Leptacanthus, &c. The successful researches of Mr. Kirkby and of Mr. Atthey have extended our knowledge of the Ichthyology of the Coal Measures. From sections of jaws and teeth, prepared by Mr. Craggs, and found in the shales and coal of the Low Main Seam, Professor Owen has recently described eleven new genera of fishes about the size of the minnow, one of which is of the Sauroid type; and associated with them are remains of what he considers a minute air-breathing Batrachian, with teeth like those of Dendrerpeton and the frog, and which he has named Gastrodus propositus. Associated with fish-remains are usually numbers of Entomostraca (Beyrichita arcuata, and Cytheropsis scoto-burdigalensis), which appear to have acted like scavengers in the carboniferous waters, clearing away the decomposing flesh of the fish. Remains of insects, nearly allied to the genus Blatta, have been detected by Mr. Kirkby in an ironstone band, near the top of the Coal Measures, on the north bank of the Wear, opposite Claxheugh. Plants, however, are the distinguishing organisms of the Coal Measures; they had grown in vast abundance on the ancient swampy ground of the Carboniferous era, and they supplied the material which forms the coal beds. A few coniferous trees flourished at this era, and the following species have been determined: Picea Withami, Pinites ambigua and anthracina, Dadoxylon approximatus and Brandlingi; but the most abundant plants are Sigillariae, of which thirteen species have been noticed; and they appear to have furnished a large proportion of the vegetable matter forming coal, since their roots, the Stigmaria ficoides, are in great numbers in the clay underlying each coal seam. Of Lepidodendra there are eleven species, and of Calamites seven. Fronds of ferns were in great profusion, and of these fifty species have been recorded, though probably not a few have been determined from different parts of the same plant.
The Carboniferous system has been uplifted and dislocated at different periods. The last upheaval of the Cheviots tilted up the lower strata; and the basaltic protrusions of a later time produced considerable disturbance. But the effects of the greatest elevating force affecting our district are seen in the Penine chain, extending from Tindale Pell southward about 60 miles; for along this line of mighty fracture the Mountain Limestone beds on the east side have been thrust upward, in some parts, near to 3000 feet—and this stupendous mountain wall rises some 2500 feet above the New Red Sandstone plain lying on the west. The Stublick and the Ninety-fathom Dikes are probably secondary effects of this disruption. By the Ninety-fathom Dike, which extends westward from Cullercoats, the Coal Measures have been thrown down on the north side from 500 feet to 1000 feet. Probably, too, the effect of the Penine upheaval has extended further northward into Northumberland, though without producing any great break in the strata in the direct line of action; for the general direction of the strata is from north to south. There are many other smaller displacements of the Coal Measures, but the Mountain Limestone strata are even more disturbed by faults: one seen in the Shilbottle colliery, ranging from east to west, throws down the beds on the south side 120 feet; another great fault near to Annstead, going westward, throws the strata down on the north side about 1000 feet.
IV. PERMIAN FORMATION.
Of this formation only one member, the Magnesian Limestone, appears in our district. It was usual to group with it an irregular, loose, sandy deposit, and some red sandstones lying below it; but the discovery of several true Coal Measure plants, such as Pinites Brandlingi, Trigonocarpon Nöggerathi, Catamites approximatus, and Sigillaria reniformis, in these sandstones, at Tynemouth, and of Neuropteris giganica, Sphenopteris latifolia, &c., in the shales connected with them, shows that these red sandstones should be grouped with the Coal Measures, the place assigned to them by Dr. William Smith, the father of English geology. Mr. Howse, in 1857, proposed, that they should be considered as the uppermost members of the Carboniferous formation, with which they are seen to be conformable in the section on the coast at Tynemouth.
The Magnesian Limestone occurs in Northumberland in three small patches overlying the Coal Measures; one at Tynemouth forming the top of the cliff, and the others at Cullercoats and Whitley, where it has been preserved by the Ninety-fathom Dike, which has thrown down the strata on the north. It occupies in Durham a large space, somewhat triangular in shape, one side extending from South Shields along the coast to Hartlepool, the other having a wavy line from the same point to Pierce Bridge, on the Tees: the base line is obscured by drift, but seems to curve away from Hartlepool westward to Chilton, and thence southward to near Coniscliffe. It occupies an area of about 230 square miles, and has a thickness of about 600 feet.
The Magnesian Limestone strata rise to the westward and south-west, and their outcrop over the Coal Measures is seen marked, in the features of the country, by a pretty bold escarpment running in a broken line of eminences of moderate elevation, but nearly on the same level throughout the range. To the west is the wide and tame region of the Coal Measures, but eastward are low undulating hills, intersected by picturesque and beautiful denes and ravines, in some of which rare plants find sheltered habitats, as in Castle Eden Dene, where grows the much-prized Cypripedium calceolus. Excepting, however, when covered with detritus, the soil immediately over the Magnesian Limestone is far from being rich or productive.
No formation has been more carefully examined than the Magnesian Limestone of our district. The important researches of Sedgwick have explained its physical characters, and its range and relations; and to Professor Philips, Professor King, Mr. Howse, and Mr. Kirkby, we are indebted for an extensive knowledge of its fossils. The result of these labours has been the determination and description of about one hundred and twenty species of marine organisms. The successive subordinate divisions of this formation have been described by Sedgwick, King, and Howse, to whose memoirs reference may be made for details, and for the views of these authors.[2] Beginning at the lowest we have the following succession of groups of strata:—
1. Marl Slate, a calcareous shale but slightly magnesian, seldom more than 3 feet in thickness, but remarkable for the number of fish-remains with which it is loaded. Thirteen species have been found in it—nine of the genus Palcsoniscus, the others being species of Platysomus, Acrolepis, Pygopterus, and Coelacanthus. With these are Discina nitida and Lingula mytiloides; the fern Neuropteris Huttoniana; and also Caulerpa selaginoides, and other obscure plant-remains, which have been regarded as fucoids. These associated organisms indicate estuarine conditions.
2. Compact limestone, which is earthy or crystalline, brown, grey, mottled or ribboned, and slaty in the bottom beds. The crystalline is chiefly carbonate of lime, but the earthy sometimes contains as much as 44.9 per cent, of carbonate of magnesia. It has a thickness of from 150 feet to 200 feet, but contains few fossils, only eighteen species having been found in it: it appears, however, to have been throughout a pelagic deposit.
3. Fossiliferous limestone, which has a thickness of about 150 feet, is generally light yellow, compact or crystalline, with little appearance of stratification. It is so rich in fossils that about ninety species have been found in it, indicating a pelagic deposit.
4. Concretionary and pseudo-brecciated limestones, are about 150 feet thick, mostly of a light yellow colour, and containing corals and mollusks, indicating generally pelagic conditions; but in some laminated or slaty beds fishes have been found in considerable numbers, of the genera Palaeomscus and Acrolepis, accompanied with a calamite, and with other plants supposed to be fucoids.
5. Crystalline, compact, and oolitic limestone, which is often laminated, and sometimes ripple-marked. Corals and Erachiopods are absent, but it contains species of Myalina and Schizodus, which point to shore or shallow water. It is about 100 feet in thickness.
The organisms of the Magnesian Limestone bring it into close relationship with the Carboniferous system, of which it properly ranks as a group or formation. Sedgwick, in 1828, pointed out this alliance, and further researches have confirmed his view: Mr. Kirkby has shown that fifteen species of animals were common to the Mountain Limestone and the Magnesian Limestone groups. Generally, the Magnesian Limestone was a pelagic deposit, with, however, evidences of shallow water at intervals, and alternations from a deep sea to an estuary.
Some plants affect a Magnesian Limestone soil. Sedgwick says, that so characteristic is Brachypodium pinnatum of that soil, that by its help he could trace the yellow limestone with great exactness; but it has not been found within our district. The following are peculiar Magnesian Limestone species: Linum perenne, Hypericum montanum, Carduus eriophorus, Orchis pyramidalis, Ophrys apifera, Ophrys muscifera, Cypripedium calceolus.
MESOZOIC ERA.
V. TRIASSIC FORMATION.
Red sandstones overlie the Magnesian Limestone in Durham and pass under the Lias of Cleveland. They are much obscured by a covering of drift, and fossils have not been found in them; hence their extent cannot be traced with exactness, nor is their synchronism determinable with certainty. Still, from their relative position, and their mineral character, they may be referred to the Trias, which forms the substratum of the great central plain of England. The lower beds are generally coarse in the grain, and of a brick red colour, and sometimes marly; and above these are gypseous marls. Sections of them appear on the coast near Seaton Carew, and on the banks of the Tees. Unsuccessful sinkings were made through these beds in search of coal; but though 444 feet were gone through at Dinsdale, and 708 feet opposite Sockburn, the Magnesian Limestone was not reached.
These beds occupy the flat country in the south-eastern part of Durham from Hartlepool to the Tees, with an extension westward of 17 miles. The whole area is about 180 miles.
CAINOZOIC ERA.
No hard stratified rocks more recent than the Trias appear in our district; but over a considerable portion of it, excepting on the higher grounds, there are accumulations of clay, gravel, and sand in layers of irregular thickness and extent. The exact sequence of these superficial deposits is not easily determinable, but we may recognize two groups of different ages.
1. The Plistocene, the oldest of these deposits, includes the boulder clay, which is usually tough, red or blue, and sometimes above 80 feet in thickness, but either unstratified, or with an irregular and imperfect kind of stratification. Through this are irregularly distributed fragments of rock, both small and large, many of them weighing several tons; and some, which are angular or but slightly rounded, are polished and striated. Generally, these blocks have been derived from rocks in situ in or near to our district; but a few, such as granite, have travelled a considerable distance. The surface of the rocks on which this clay rests has also been found polished like marble, striated, and grooved, the striae and grooves having the same general direction, and evidencing the movement of a powerful abrading agent in a southerly direction. These dressed surfaces have been observed on the limestone at Middleton, near Belford, on the basalt of the Farne Islands, on limestones at Swinhoe, Dunstanburgh, Little Mill, Hawkhill, Belsay, and on sandstones at Berling Car, south of Alnmouth, and on the banks of the Irthing. Mr. Howse has also noticed such dressings on the Magnesian Limestone near South Shields. Along with this clay, and apparently belonging to the same era, are gravel and sand beds, and fine laminated clays, which are sometimes interstratified with the greater clay deposit. Near to Durham, boulder clay, containing large polished and striated blocks, overlies stratified sands, which are about 30 feet in thickness. Excepting at Tynemouth, where Mr. Howse found small pieces of Cyprina Islandica, a marine shell still living on our coast, I know of no fossils which have been discovered within our district belonging to the boulder clay era.
So far as is at present known, moving ice is the only natural agent which produces such dressed surfaces; and therefore it may be inferred, that during the boulder clay era, the North of England had an arctic climate. Not only do the glaciers on the Alps, in Iceland, and other mountain regions, polish and striate surfaces over which they move, but even the ice-covering of an extensive area of land with a gentle slope, such as Greenland, produces similar effects by slowly moving down to the sea shore; and it is probable, too, that the great icebergs, some of which are 4 miles in circumference, and 1800 feet high, would, when grounding and moving along the sea bottom, also polish and striate rock surfaces. The love of simplicity has, perhaps, led theorists to attribute too much to one cause. The question presented for solution by the phenomena of the boulder clay is complicated; for, as conditions in the problem, there are not only glaciated surfaces and glaciated boulders mixed pell mell in the lower clay, but there are similar boulders in gravel and sand beds, and also stratified sands and clays, and water-worn gravels; and in addition, the occurrence of marine shells in even the lower clay. A comprehensive theory must, therefore, allow for the play of various agencies—the movement of ice down mountains, and over extended areas of land to the sea shore, the stranding of icebergs, the transport of gravel and sand by marine currents, and even the quiet deposit of mud in stiller waters, during the long period comprehended in the boulder clay formation.
2. Post Plistocene.—Since the boulder clay era, there has been little change in the general contour of the district: some valleys have been deepened, some shallow lakes and marshes drained; and along the coast can be found traces of slight oscillations of level. Gravel, very much rolled and rounded with beds of sand, chiefly seen in. river valleys, accompanied with terraces on the river banks, belong to a later period than the boulder clay. More recent, still, are accumulations of peat, which is formed at all levels from the sea coast to the summit of our highest hills, under the conditions of moisture and cold. A depression of the land is indicated by peat and overthrown trees (sub-marine forests) seen in some parts of the coast, below the line of the lowest tides: a marked case of this character is near to Howick. Frequently below the peat is a deposit of marl, which, in some instances, is filled with fresh-water shells, all of recent species. But besides these there have been found, either in the peat or in the marl, Bos primigenius, Bos longifrons, Megaceros Hibernicus, Cervus Alces, Cervus elephas, the wild boar, and remains of a horse.
IGNEOUS ROCKS.
There are two groups of igneous rocks in this district, of different age and mineral composition—the felspathic and the augitic; or the porphyries and the basalts; the former being of a much greater age than the latter.
1. Porphyry.—The Cheviots, a range of hills protruding through, and rising high above, the stratified rocks in the northern part of Northumberland, and extending into Roxburghshire, are composed of porphyry, which, however, varies in its character. Usually, the rock is a porphyrite, with a red felspathic base, in which are scattered crystals of felspar. In some parts it is a dark coloured dolerite, composed of labradorite and augite; and near to Yetholm it is a pitchstone porphyry. Not unfrequently it passes into a syenite, a crystalline compound of felspar, hornblende, and mica; and in some few cases it becomes a granite, formed of felspar, quartz, mica, and a little hornblende. On the north side of the Cheviot, in the Diamond Burn, there are masses of quartz rock in which appear crystals of quartz, some white or translucent, and a few others brown or amethystine. On the Ridlees Burn, where stratified rocks abut against it, the porphyry is amygdaloidal, with geodes, in which are developed fine quartz crystals, or which are filled with agates and calcedonies. The great mass, however, is felspathic.
The boundary line of this porphyritic range begins on the borders, at Presson, and goes eastward to Brankston, where the battle of Flodden was fought; it then bends southward to Yeavering, and by a series of undulations passes by Akeld, Wooler, Ilderton and Brandon, to Ryle, whence it bends westward to Prendwick, and thence, in a south-west direction, crosses the Coquet, above Linn Brig, to Ridlee Hill; after which it bends to the north-west, and crossing the Coquet again, above Philip, extends into Roxburghshire. Another part of the range is prolonged from Roxburghshire into the north side of the Reed above White Lee. The whole occupies an area of about 200 square miles in Northumberland, and of 100 in Roxburghshire. This range is marked by distinctive physical features. The lowest level at which the porphyry appears is 200 feet above the sea, in Akeld Burn; but, rising steeply from the stratified rocks, it soon attains a high elevation, generally of not less than 1000 feet: Humbleton Hill, near Wooler, the scene of a famous border battle, is 977 feet high; Yeavering, of archaeological and historical celebrity, is 1182 feet; the Newton Tor is 1762 feet; Dunmore is 1860 feet; Windygyle, near the borders, is 1983 feet; rounded Hedgehope is 2348 feet; and broad-backed Cheviot, the highest, is 2676 feet above the sea level. Many of these high hills are of fine conical forms and roll into each other, being separated by short upland valleys or hopes; in others the division is made by narrow rugged and craggy clefts. Through deep valleys or gorges the burns and rivulets brawl over rocky channels, leaping over crags into highly picturesque linns, such as the Harthope and Linnhope Spouts. Naked though the mountains are, being treeless, nevertheless "sublimity breathes from their forms." Where the declivity is considerable long trains of angular rocks, detached from the mass, extend from near the summit to the base; and these, when weathered, have a purple hue, which blends well with the bright green herbage which here and there appears. Locally, these trains are called glitters or glidders, probably from gleiden (Anglo-Saxon), to slide.
Though the rock is hard, yet the felspar is liable to decomposition by the ordinary action of the elements, and the soil resulting is highly productive. The top of the higher hills is covered with peat and yields a coarse grass; but on their slopes, and on hills of less elevation, a fine grass grows well adapted for sheep pasturage. Though in the valleys, and ravines, and sheltered nooks several plants of rarity and interest flourish, yet this range, considering its extent, elevation, and composition, has not a rich Flora. Some plants, peculiar to igneous rocks, will be noticed when treating of the basalt; but others, which are confined to the Cheviots, have their habitat there more from elevation than from the mineral character of the rock; as for example, the Cornus Suecica, and Epilobium alpinum. The basaltic rocks yield a more peculiar and varied Flora.
The Cheviot porphyry is undoubtedly the oldest igneous rock in our district. It was protruded subsequently to the Cambro-Siluria era, for the Greywacke beds are highly inclined against it; but prior to the deposition of the Upper Old Red Sandstones, as the conglomerates are partly composed of rolled Cheviot porphyries. The Cheviots, however, had been further elevated subsequently to the Tuedian period, for beds of that age are highly inclined against the porphyry on the Coquet and in Akeld Burn.
2. On the boundary of Northumberland, near to Carham, there is another outbreak of igneous rock unconnected with the Cheviots, and of a later age, but of a porphyritic character, having a greenish claystone base resembling wacke, with crystals of red felspar. It crosses the Tweed at Carham, and the railway near to Reddon Burn, and then runs along Heddon ridge a distance of about 3 miles. It protrudes through beds of the Tuedian group; and near to it is the peculiar Magnesian Limestone with chert nodules.
AUGITIC ROCKS.
The Basaltic Whin Sill is the most remarkable rock in the North of England on account of its long and tortuous range, and of its relation to, and effect upon, the strata it traverses, and among which it has been intruded. A sill it has been called, because sometimes seen, like a stratum, intercalated among stratified rocks. It is not, however, a true stratum, for its thickness varies very much, from 2 or 3 feet to more than 200 feet, and the parallelism of its upper and under surface is preserved only for a short distance; so that, though its extension in the line of direction is great, yet its extension in the line of dip is inconsiderable.
It is traceable through Northumberland, with breaks here and there, from Kyloe to Glenwhelt; and the same kind of rock extends southward into Durham, Cumberland, and Yorkshire.
Let us trace its range, and, as we go along, note any peculiarities. It first appears in the North at Kyloe Crags, in a fine mural cliff 400 feet above the sea level, resting on sandstone, and overlaid by a shale, which is metamorphosed; it then extends south-eastwards, and at Middleton is intercalated between a limestone and a sandstone, the latter being above it and metamorphosed at the point of junction. From Belford it goes eastward in a succession of high cliffs to Spindlestone, where it rests on limestone, and then to the mouth of the Warn, whence it bends southward to Bamburgh, where it is 75 feet thick, resting on sandstone and shale. Along the coast, between Budle and Bamburgh, there appear two different overflows or veins, separated by metamorphosed shale, and above the basalt is limestone. From Bamburgh it extends seaward, and forms the mass of the rocky islets of the Farne. It reappears on the south side of Beadnell Bay, having above it what we shall call, for distinction's sake, the Bent Hall limestone, which is here magnesian; and after curving inland, and again running along the coast southward of Newton, it sweeps round by Emblcton and Spittalford to Dunstanburgh Castle, where, in two places, metamorphosed shales come out of the mass of basalt; and limestone, when in contact with it, is changed into white crystalline marble. It extends along the coast to Cullernose, where it is 120 feet thick, and where, too, remarkable results of mechanical action are seen in the dislocated sandstone strata. Here it bids adieu to the coast, and trends away south-westward by Howick and Longhoughton; and at Rateheugh there are evidences of two, if not three, overflows or injections, two being distinctly seen in a section at Dunsheugh, where the limestone above as well as the shale below is metamorphosed. It crosses the Aln near to Denwick Mill, and is next seen southward of Alnwick at Stoney Hills, whence it runs to Snipe House and Shieldykes among the lowest beds of the calcareous division of the Mountain Limestone; but between this and the south bank of the Coquet no traces have been found of this sill. It, however, reappears at Ward's Hill, with the Bent Hall Limestone below it, and goes thence to Hartington, beyond which, for some distance, there are two lines of basalt, one passing the Elf Hills and Bavington, and the other West Whelpington and Throckington; but from Little Swinburn there is only one range towards Gunnerton. At Whelpington, on the Wansbeck, two beds of Basalt are seen, separated from each other by a bed of metamorphosed shale one foot thick, the basalt being below limestone and resting on sandstone. It crosses the North Tyne below Haughton Strother, and appears on the line of the Roman wall at Limestone Corner, and then, after a curve southward, it joins the line of the wall again eastward of Shield-on-the-Wall, thence running westward, as far as Thirlwall, in a succession of high-pillared craggs, with deep gaps or "nicks" between, and with cliff faces to the north and north-west, and reaching, at Winsheals, an elevation of 1000 feet above the sea level. About a mile to the west of Glenwelt, it crosses the turnpike road, beyond which it is little seen in our district till we reach the upper part of Teesdale. Though the basaltic sills in Durham are similar to those in Northumberland, and are intruded among the Mountain Limestone in a similar manner, yet it is not certain that all belong to the same eruption. Near the borders, between Northumberland and Cumberland, basalt forms the bed of a burn, in Knaresdale, for about 400 yards, and also of Gildergate Burn for about 100 yards; but it appears more in Cumberland, in the streams which carry off the drainage of the western side of Cross Fell and Hartside. At Wear Head a basaltic sill appears broken by the Burtree Ford basaltic dike; but further down the Wear, near Stanhope, there is another basaltic sill, which Sir Walter Trevelyan thinks is different from the Great Sill, and situated among beds higher in the Mountain Limestone series. From Unthank Bridge this little sill forms the bed of the river for some hundred yards, and is traceable westward, as far as Westerhope, thinning out in that direction; it is 20 feet thick in Rookhope Burn, where it is intruded between limestone beds, the lower one being metamorphosed.[3]
The Great Basaltic Whin Sill attains its maximum thickness in the Tees, where it is above 200 feet thick, giving a picturesque character to the wild scenery of Upper Teesdale. It is seen above the Weal, an extensive pool formed by a natural dam in the river, and is there overlaid by a granular white limestone. At High Force and Cauldron Snout the river cuts through it, and tumbles over cliffs, exposing a limestone below, which is metamorphosed, white and crystalline. This basalt extends nearly as far as Middleton, but in the lower part, at a little distance from the river.
Throughout its long range the rock is essentially the same, being composed of felspar and augite; the iron entering into its composition is in the state of a protoxide, and indeed occasionally, as at the Farne, it possesses polarity. At Budle it is amygdaloidal; and at Ratcheugh some portions are porphyritic, having large felspar crystals scattered through it. Where in great mass the rock has a pillared structure, the columns being rude prisms, irregularly jointed; and some even approach the hexagonal forms seen in Fingal's Cave. They are grand and impressive objects, massive, though rude; and, towering majestically to a great height, we could imagine they had been piled up by the fabulous giants of the olden time.
The metamorphic action of the basalt on the strata above, as well as on those below it, is favourable to the view, that the Basaltic Sill is a lateral dyke intruded among the strata after their deposition; and the displacements of strata effected by the eruption lead to the same conclusion. At the Farne Islands, 90 feet of limestones, shales, and sandstones have been torn from the mass with which they were originally connected, and are lifted up and altered in structure. At Howick, too, there are evidences of violent mechanical action; and near to Little Mill there is a marked instance of the same character—for on the western or basset side of the basalt, limestone and shales are highly inclined against it: their dip is to the south-west from 60° to 45°, and the upper shale-beds are bent and thrown over; blocks of limestone, too, are enveloped in the basalt, and metamorphosed and penetrated with veins of the igneous rock, the whole being firmly welded, as it were, into one mass. Though in Northumberland this sill never appears anywhere, excepting in the calcareous division of the Mountain Limestone, and generally among its upper beds, yet its position varies considerably in different parts of its course; indeed it cuts across these strata in some places, and alters its relative vertical position to the extent of 1000 feet.
There appears, however, to have been more than one eruption, though probably succeeding each other at no great intervals of time: Stanhope, Kirkwhelpington, Ratcheugh, and other places give evidences of this. At Ratcheugh there may have been three eruptions, but two pseudo-strata are distinctly seen there; one of them is wedge-shaped, and, in the course of 500 yards, dwindles down from 90 feet to 30 inches in thickness, while the second mass overlaps the other and is separated from it by 22 feet of intervening limestone and shale. In a pit-sinking at Long Dike, in search of the Shilbottle coal, two layers of basalt were passed through; one, 15 feet thick, is between metamorphosed arenaceous beds; and the other, 63 feet lower down, and 2½ feet thick, penetrates, metamorphoses, and partly replaces a seam of coal.
2. Another mass of trap rock, a greenstone or diorite of considerable thickness, caps the Carter Fell at the height of 1600 feet above the sea level overlying Mountain Limestone strata, which rest on the upturned edges of Cambro-Silurian rocks.
BASALTIC VERTICAL DIKES.
Besides the great lateral dike or dikes, a considerable number of basaltic dikes cut through the Carboniferous strata nearly perpendicularly, most of them having a direction from eastward to westward. The character of the rock of nearly all of them is similar to that of the Whin Sill, but generally finer in the grain, and with the structure more altered by contact with stratified rocks; for at such points there is a mutual transference of character, the basalt itself imbibing, as it were, a portion of the mineral ingredients of the adjoining stratified rock. Of the following basaltic dikes we have some definite information. Our list begins with the most northern.
The Cornhill Dike is seen in a cliff on the south bank of the Tweed, half a mile below Coldstream Bridge, cutting perpendicularly through the Tuedian beds with a direction of north 82° east, and is traceable a distance of 7 miles, passing, in its course, also through Mountain Limestone strata. On the Tweed it is 10 feet wide, but it thickens eastwards, and at Melkington it is 15 feet, and at Mattalees 33 feet wide.
The Lindisfarne Dike has a course from eastward to westward, but not straight. It crosses the south part of Holy Island in the direction of south 85° east, and is seen two miles seaward, forming the Plough and Goldstone rocks, on which the Pegasus was wrecked. On the west side of the island the dike is exposed in a high cliff, and is there 120 feet wide, with a slope to the south of 95°; large blocks of limestone are enveloped in the basalt and highly metamorphosed, and the strata have a considerable upcast on the south side. A calcareous shale, highly fossiliferous, lying above a limestone, is remarkably metamorphosed—and near to the Castle veins of the basalt penetrate the shale. This dike is seen near Fenham, and afterwards a little northward of Kyloe church, where it has a direction of S. 80° W., and is from 20 to 60 feet wide, increasing in width as it descends; and in one part it is covered by sandstones and shales. It cuts through the Lowick coal field and is traceable westward to Leitham, the whole ascertained course being about 14 miles.
The Beadnell Dike is well exposed on the coast, rising like a Cyclopean wall through sandstone, limestone, shale, and coal beds, whose relative position is but slightly altered, but whose structural characters are greatly changed: coal for some distance from it is valueless, limestone near it will not burn into lime, and shale and sandstone are indurated. The mutual transference of qualities, between the basalt and the stratified rocks penetrated, is well illustrated in this dike. Its width is generally 25 feet; the direction is south 85° west; and it is traceable four miles inland as far as the Newham Station.
The Howick Dike is only 4 feet wide, sloping south 95°, and with a direction of north 80° east. It is seen only on the coast, and is remarkable for its wall-like appearance and its nearness to the Whin Sill, which, however, it is not seen to join.The Boulmer Dike is 100 feet wide, ranging north 80° east, and appears only on the coast passing perpendicularly through Mountain Limestone strata, which it has altered but slightly.
Trobes Dike is seen in the eastern part of the Shilbottle colliery, running in the direction of south 85° west, having a width of 33 feet, and metamorphosing the strata on both sides.
The Hampeth Dike is large, and passes through the Shilbottle coal field. A mile and a half south-west of Shilbottle it appears in the bed and banks of Hampeth Burn, which has forced a pass through this rocky barrier by a narrow gorge, the basaltic cliffs on both sides reaching the height of 50 feet. The width of the dike here is 150 feet, and the direction S. 80° W.: near to it the coal is charred. It seems to extend to the sea, passing through Millstone Grit beds a little southward of Berling Carr.
The Acklington Dike has a general direction of west by north, and appears on the coast at Bondicar; passing through the Coal Measures and Millstone Grit, it crosses the Coquet near to Acklington Park, where it is 30 feet wide. A dike in the line of this is seen cutting through the Mountain Limestone, at Debden colliery, and ranging onward as far as Clennell approaching near to the porphyry of the Cheviot, but never entering it. At Cartington Castle a limestone abuts against it on the north side. The range is thus about 20 miles.
The Causey Park Dike is 30 feet wide, and has a direction from east to west, cutting through Millstone Grit strata. Gritty sandstone abuts against the north cheek, and flaggy sandstone and carbonaceous shale are on the south side.
Two dikes, about a mile and a half apart, run parallel from Hartley to a mile northward of Cramlington, in the direction of west north-west, and pass through Coal Measure strata. In a line with the Southern Hartley Dike is one at Bolam cutting through Mountain Limestone beds, which are metamorphosed.
The Tynemouth Dike appears in the cliff below the Priory, rising through the Coal Measures, the red sandstone, and the yellow sand; but it is not seen either underlying or penetrating the Magnesian Limestone, which caps the same cliff a little to the northward of the dike. It is 12 feet wide, and runs in the direction of south 40° east to north 40° west, with a slope southward of 85°. The dikes we have noticed are basalt, but this is more allied to greenstone or diorite.
The Coaly Hill Dike varies in width from 7 feet to 21 feet, and has a general direction of E.S.E. It seems to be the same as that which comes to the surface at Ouseburn, and at Simonside, in the county of Durham. Buddle has described it, and notices, that it pursues an undulating course, only occasionally appearing on the surface. In Benwell colliery it is 200 feet, and in Walker colliery 630 feet below the Tyne level. The coal in contact with it is reduced to "cinder."
Two small dikes with an east to west direction, about 13 feet apart, one being 5 feet and the other 6 feet wide, dipping north 78°, are in Walbottle Bene: these have the character of greenstone.
The Brunton Dike, on North Tyne, which cuts through the Mountain Limestone beds from north 40° east to south 40° west, is 16 feet wide, and throws down the strata on the west side above 20 feet. It crosses the South Tyne passing Warmley, and probably extends to Whitfield, where a basaltic dike is seen on the West Allen.
The Lewis Burn Dike has a long and somewhat irregular course, but with a general direction of east north-east; and it is traceable from Short Cleugh, on Lewis Burn, to Troughead and Darden, in Redesdale, a distance of 12 miles. At Short Cleugh, in the deep gullies made by water torrents, this dike is exposed at several points; it widens as it descends, and attains the width of 50 feet; a small branch comes from the main trunk, and is seen in the hill side. The Mountain Limestone strata, which it cuts through, are greatly dislocated; on its south side sandstone beds are flat, while on the other they are nearly perpendicular.
Of the two principal basaltic dikes in Durham we have some definite information.The Hett Dike has a direction of E.N.E., and passes through the Coal Measures, Millstone Grit, and Mountain Limestone. It may possibly have its origin from the Whin Sill. It is seen in Eggleston Common, and where it crosses Eggleston Burn it is nearly vertical, and 33 feet wide. It is traceable eastward to Hett and Quarrington, passing through the Crow Trees colliery and dividing and charring the Five-quarter and High Main Coal Seams; but it does not penetrate the overlying Magnesian Limestone. As it extends eastward and approaches the surface it diminishes in width, and at Crow Trees it is only 6½ feet.
The Cockfield Dike, from its great length, is one of the most important, extending from north-west to south-east about 70 miles, and passing through Mountain Limestone, Millstone Grit, Coal Measures, and New Red Sandstone. It varies in width from 17 feet to 60 feet. At Cockfield the coal in contact with it is charred, and the strata are upcast 18 feet on the south.
No basaltic dike has yet been seen among the Magnesian Limestone strata.
We know not the vomitaries of these augitic igneous rocks. Along the whole range of the Whin Sill no crateriform hollows or cones appear: the molten matter, therefore, had probably been ejected through long lines opened by deeply-seated forces acting in the general direction of north to south. The vertical dikes of basalt have a direction transverse to that of the Whin Sill; and though, as Philips remarks, "geographically related to it," are never seen in junction with it. They are too small to have been the vomitaries of the Whin Sill; and supposing they are of the same age, they do not help us much to determine the period of eruption. None of them, excepting the Cleveland Dike, which is at the southern extremity of our district, pass through beds more recent than the Coal Measures. The Whin Sill, however, as Philips has shown, is anterior to the east and west veins of Tynedale, for it is divided by these veins of fissure, and, as these fissures have resulted from the Penine fault, the Whin Sill is older than the Triassic beds. Subsequently, then, to the Carboniferous, and prior to the Triassic era, this district was convulsed and rent by volcanic forces, most probably when beneath the sea; and, at remitting intervals, molten lava was poured out of fissures generally in a line from north north-east to south south-west, partly over the sea-bed, and partly thrust in among the stratified rocks which it metamorphosed; and, cooling slowly, under the influence of considerable pressure, this lava assumed the stony crystalline character of basalt. Mr. Hopkins has shown how minor fissures are formed transverse to the chief line of fracture, and therefore it is highly probable that the transverse basaltic dikes are due to the same causes which produced the Whin Sill.
Some plants in Northumberland are confined to the igneous rocks, and chiefly to the augitic group. Dianthus deltoides is common to the porphyry and basalt: I have seen it on the very verge of the porphyry, but I could not, after diligent search, find a single specimen straying across the border to a stratified rock. Pyrola secunda, and Teesdalia nudicaulis, have not been noticed except on porphyry. But the following occur in Northumberland only on the basalt: Moenchia erecta, Sagina subulata, Vicia lathyroides, Asperugo procumbens, Statice limonium, Convallaria polygonatum, Allium schoenoprasum, Scilla verna, Sedum anglicum, Asplenium septentrionale, Asplenium germanicum. Helianthemum vulgare, although also occurring in limestone, I have sometimes found a useful guide in tracing the range of the Whin Sill.
POSTSCRIPT TO CHAPTER I.
ADDITIONAL OBSERVATIONS ON THE INFLUENCE OF THE SUBJACENT ROCKS ON PLANT DISTRIBUTION, BY J. G. BAKER.
From the more strictly botanical point of view I propose to supplement Mr. Tate's sketch by a few observations on the influence exercised by the character of the subjacent rocks on the distribution of the Flora. The sedimentary beds of the north-east of England fall under two well-contrasted types in their influence on the scenery and botany. These,[4] following the nomenclature of the writer who has investigated the subject most carefully, we will name dysgeogenous and eugeogenous, names derived from the comparative readiness with which they produce detritus, and yield to disintegrating influences. In the North of England the first is typically represented by the limestones of various ages, and the other by the sandstones and shales from the Kimmeridge clay down to the Old Red. We see the two opposite types of scenery contrasted better in Yorkshire than in Northumberland and Durham. In the North Riding the eastern third is occupied by two parallel ranges of hills, running from west to east, for a length of 30 miles, from the central vale to the coast, one formed from the arenaceous rocks of the lower oolite formation, and the other from the calcareous upper oolite, which show the characteristic features of the two types excellently. The flat table lands of the limestone hills contrast with the irregular undulations of the sandstone hills: the steep precipitous calcareous scars, not less so with the irregular "edges" of freestone and gritstone. The sandstone hills are intersected by branching rivulets, which flow from their upper levels gradually down their slopes into the low country. The limestone hills have neither streams nor natural pools upon their surfaces, but the glens slope suddenly, and the water sinks through the calcareous beds to gush out in large volume when it reaches some less permeable stratum. The sandstone dales are open and irregular, with gradual slopes and undulated embankments; the limestone dales are steep and narrow, with sudden slopes and enbankments rising up like a wall upon each side to shut them in. In Northumberland and Durham we have only a limited and not very characteristic development of limestone hill and dale. The great series of beds deposited during the Mountain Limestone period, so characteristically calcareous in Derbyshire and the West Riding of Yorkshire, gradually loses this character as it passes northward, and as Mr. Tate has already explained, has changed completely by the time that it reaches Northumberland. Unless this state of things is kept in view, any one looking at our geological map may easily get a very wrong idea into their mind about the physical geography of our field of study. We have an instance of a similar difference in lithological character between two contemporaneous deposits in the lower oolite, which is thoroughly calcareous in the South of England, but in Yorkshire has only a single bed of impure limestone 30 to 60 feet in thickness in the midst of an arenaceous series 800 feet in depth. In our two counties we get this limestone type fairly shown only in the comparatively small Magnesian Limestone tract of the east of Durham, and its features developed, to a certain extent, in the upper part of the western Durham dales, especially in Teesdale and Weardale. The wide extent of hill-country between the Cheviots and the Tyne, several hundreds of square miles in area, and the fells and the slopes of the west of Durham, with the exception just indicated, show everywhere in their contours and Flora the distinctive features of the eugeogenous type. We will, therefore, in the first place, attempt a detailed sketch of the vegetation of a hill of this kind. Our notes refer to Simonside, which was selected as being a fair typical representative of the shale-sandstone type of moor which occupies so large a proportion of the northern English counties.
General Sketch of a Eugeogenous Hill and its Vegetation.—From Rothbury to the summit cairn, at the east end of the hill, the distance is about 4 miles. Walking up the dale on the south side we have to keep the high road as far as the little village of Tosson, and then are in a straight line between the peak and the Coquet. At 500 feet above sea-level, and 200 above the river, we pass the highest farm house, and very soon the corn fields cease, and we climb through a meadow along the bank of the streamlet which flows down from the hill to the Coquet, a tiny brook overshadowed by ash-trees and bushes of bird-cherry, hazel, and blackthorn, with Crepis paludosa growing amongst them, and a beautiful form of Rosa tomentosa, with pure white petals just tinged towards the edge with red. Then a half-drained rushy pasture (one of the rushes in which is Juncus diffusus) is crossed, and we enter upon the open moor. From where the heather begins, to the highest point of the hill, the ascent is 900 feet, and the distance is not less than a mile, but it looks much less, for as usually happens in climbing hills, the highest part cannot he seen from the bottom, and we reach several successive ridges, each with a craggy edge of gritstone, only to find that there is another terrace to cross and another ridge to climb before the real highest is gained. All down this sloping bank the fallen rocks are scattered, rounded masses of fine-grained gritstone, so soft in texture, that it crumbles away easily into a silvery-grey powder, which is often scattered over the bare turf, the micaceous particles glittering in the sunshine; and from the summit crag all down the bank the heather sweeps (brown for ten months of the year, bright purple for two), thick-swelling over the terraces and in the hollows, stunted and scraggy amongst the rocks and where the soil is thin. The three kinds of heath are all here in plenty, and in July the Ericae are already in flower whilst the Calluna still remains in bud, and there are Vaccinium myrtillus and Empetrum nigrum scattered amongst them, and Eriophorum vaginatum and feathery tufts of Nardus waving in the mountain breezes, and scattered clusters of Aira flexuosa, conspicuous by its bright red stems and silvery brown panicles. At the bottom the furze bushes and the foxgloves grow tall and fine, but they stop before we reach the higher levels; and the slopes and hollows are filled with bright-green forests of Pteris, which grow up to form intertangled thickets in the late autumn, and sometimes with Blechnum, and the lady-fern, and Lastrea oreopteris scattered amongst it. The damper spots are spongy with mosses, Hypnum fluitans, Polytrichum commune, and Sphagnum, ranging in colour from deep red to bright green, with pale green cushions of Leucobryum and Aulacomnion palustre, and amongst them Drosera rotundifolia, Carex ampullacea, Eriophorum angustifolium, and the clustered sword-like leaves of Narthecium. The streamlets which issue from the hill-side ripple noisily down their shallow, stony channels, or contract and sink down, and are hidden for awhile beneath overhanging grass and rushes. The principal mosses of the well-heads are Hypnum condensatum, H. cuspidatum, Bartramia fontana, and Bryum pseudo-triquetrum, the first brownish, the others pale green, or the last often brightly tinged with red. Amongst them Chrysosplenium oppositifolium, Montia fontana, and Stellaria uliginosa grow inter-mixed, and in the swamp by the stream side are Carex dioica, stellulata, pulicaris, flava, and glauca, Molinia caerulea, and yellowish-green soft glossy tufts of Pinguicula. The drier and more grassy parts of the hill-side yield Galium saxatile, Triodia, Anthoxanthum, Carex binervis, Potentilla tormentilla, and abundance of Festuca ovina. The highest ridge is formed of large rounded crags of a coarser-grained rock than the scattered masses below, often variegated with lichens, obscure-crusted black-pointed Lecidece, interspersed sometimes with the brighter hues of Lecidea geographica, wide-spreading silvery-grey patches of Cetraria glauca and Parmelia saxatilis, and darker ones of the omphalodes variety of the latter, coral-like cushions of Sphaerophoron, and the ink-coloured leathery thallus of Umbilicaria proboscidea. The crags are too dry to produce many mosses, the principal kinds which occur being Hypnum cupressiforme and Dicranum scoparium upon their exposed faces, and in the shady crevices Jungermannia albicans and Mnium hornum. In the sheltered hollows Lastrea dilatata may sometimes be seen and Luzula syhatica amongst the scattered ling bushes, and casually Listera cordata and Vaccinium vitis-idaea under the shade of the heather.
This, then, is the kind of vegetation which, with extremely little variety, covers a large proportion of the uncultivated and especially the upland parts of our two counties. The most distinctly marked influence upon the topography of the species produced by the distribution of the subjacent rocks, is the more or less absolute restriction of a certain number to the limestone tracts. Out of our eight hundred and forty-four native species there are forty-four which show clearly this lithological restriction. In North Yorkshire, as might be expected from the greater predominance of the calcareous element in the strata, the number of these Xerophilous, or dry-loving species, as Thurmann calls them, is considerably greater. There are three tracts of limestone in the North Riding, the Carboniferous, Permian, and Oolitic, which are surrounded by, and separated from, one another by wide tracts underlaid by arenaceous and argillaceous beds, so that it is a district exceedingly well -adapted for showing clearly which the restricted species are. The following are the Northumberland and Durham species, those marked with a star being confined to the Magnesian Limestone.
Plants peculiar to the Limestone.
| Aquilegia vulgaris. | Campanula glomerata. | |
| Draba incana. | *Ligustrum vulgare. | |
| Arabis hirsuta. | Polemonium caeruleum. | |
| Helianthemum vulgare. | Gentiana verna. | |
| Viola hirta. | amarella. | |
| Cerastium arvense. | Atropa belladonna. | |
| Arenaria verna. | Salvia verbenaca. | |
| *Linum perenne. | Origanum vulgare. | |
| *Hypericum montanum. | Calamintha nepeta. | |
| Geranium sanguineum. | Taxus baccata. | |
| Anthyllis vulneraria. | *Orchis ustulata. | |
| Astragalus glycyphyllus. | pyramidalis. | |
| hypoglottis. | *Ophrys apifera. | |
| *Onobrycbis sativa. | *muscifera. | |
| Spiraea filipendula. | Cypripedium calceolus. | |
| Rubus saxatilis. | Convallaria majalis. | |
| Poterium sanguisorba. | Sesleria caerulea. | |
| Pyrus aria. | Avena pratensis. | |
| Galium sylvestre. | Melica nutans. | |
| Scabiosa columbaria. | *Bromus erectus. | |
| *Carduus eriophorus. | Hordeum sylvaticum. | |
| Carlina vulgaris. | Polypodium calcareum. |
The following are the plants of this class which occur in North Yorkshire, but not with us at any rate in a truly wild state:—
| Anemone pulsatilla. | Asperula cynanchica. | |
| Actaea spicata. | Inula conyza. | |
| Helleborus viridis. | Orobanche rubra. | |
| Hutchinsia petraea. | Calamintha officinalis. | |
| Helianthemum canum. | Epipactis ovalis. | |
| Hippocrepis comosa. | Spiranthes autumnalis. | |
| Potentilla verna. | Carex digitata. | |
| Dryas octopetala. | Brachypodium pinnatum. | |
| Galium erectum. | Ceterach officinarum. | |
| Dipsacus pilosus. |
The following is a list of all the species seen within the bounds of the upper zone on Kilhope Law, and it might stand, with very trifling variation, for any other of the higher peaks and ridges of this character.
Florula of the Upper Zone on a Eugeogenous Hill.
|
Viola palustris. |
Juncus squarrosus. |
|
M. Thurmann has given for a portion of Central Europe a full list of the indigenous plants, and an account of their distribution with regard to the subjacent rocks. In Central Europe there are two extensive ranges of hill, of well-marked contrasting lithological character, the dysgeogenous Jura, and eugeogenous Vosges. Comparing the British flora as a whole with that of this region, and, indeed, with that of any other part of Central Europe, we see, even by glancing over the mere list of names, how conspicuously with us the damp-loving element predominates. He gives for the rocks of each class a list of the fifty plants which he finds to be most characteristic; and of those which he names for the dysgeogenous strata, we have in Northumberland and Durham eight species only, whilst out of the eugeogenous fifty which are frequent in the arenaceous Vosges, but either nearly or quite absent in the calcareous Jura under parallel, or nearly parallel, conditions of atmospheric climate, we have thirty-five species, which are the following:—
List of Northumberland and Durham Plants which are characteristically Eugeogenous in Central Europe.
|
Orobus tuberosus. |
Alopecurus pratensis. |
|
We have in this list most, or very nearly all, the very species which make up the gregarious swamp-heather-land vegetation of which we have spoken as covering, with us, such wide tracts of surface. Of the four kinds of rock—limestone, porphyry, slate, and sandstone mixed with shale, that in the North of England form hill-masses on a grand scale, there are none from which these plants as a class are excluded, though it is amongst the sandstones that the ericetal species especially attain their greatest luxuriance and frequency. To sum up the bearings of the subjacent rocks on plant-topography, as exercised with us, as compared with what takes place in Central Europe, we shall be safe in saying, 1.—The species which in Central Europe are restricted to dysgeogenous tracts occur with us in small number only, and are restricted lithologically in a similar manner. 2.—The species which in Central Europe are restricted to eugeogenous tracts occur with us in large number; and under our more boreal and humid climate grow abundantly, and cover wide areas of surface without keeping up any clearly-marked role of lithological restriction. And this shows us in what direction the interference of the rocks operates. A more porous and more humid soil evidently, to some extent, compensates for a drier climate; and in proportion as the climate is damper the characteristically dry-loving species are more restricted to dry-soiled tracts of country. This is the rule, and in botanico-geographical considerations it is evidently worth bearing in mind; but to what extent it has been influential in determining which species we should have or which we should not have, either in our two counties or in Britain as a whole, or to what extent it has, for instance, operated in the restriction to the area which they occupy, of the plants of what Mr. Watson calls the Germanic type of distribution, we can but guess vaguely.
About the basalt and porphyry we have said nothing as yet. The following is a type florula for one of our lower zone porphyritic crags, the cliff selected being one by the side of the Coquet, between Windyhaugh and Shillmoor, at an elevation above sea-level of from 630 to 700 feet.
Florula of a Lower Zone Porphyritic Crag.
| Draba verna. | Rosa spinosissima. | |
| *Arabis hirsuta. | Pimpinella saxifraga. | |
| Sisymbrium thalianum. | Hedera helix. | |
| *Helianthemum vulgare. | Galium cruciatum. | |
| Dianthus deltoides. | verum. | |
| Cerastium triviale. | *sylvestre. | |
| Sagina procumbens. | Hieracium pilosella. | |
| Viola sylvatica. | vulgatum. | |
| Geranium Robertianum. | Leontodon taraxacum. | |
| Hypericum pulchrum. | Apargia autumnalis. | |
| Spartium scoparium. | Carduus lanceolatus. | |
| Carduus arvensis. | Urtica dioica. | |
| Centaurea nigra. | Festuca ovina. | |
| Achillea millefolium. | *Avena pratensis. | |
| Campanula rotundifolia. | flavescens. | |
| Veronica arvensis. | Aira precox. | |
| Digitalis purpurea. | Anthoxanthum odoratum. | |
| Teucrium scorodonia. | Poa nemoralis. | |
| Myosotis arvensis. | Agrostis vulgaris. | |
| Plantago lanceolata. | Polypodium vulgare. | |
| Rumex acetosella. | Pteris aquilina. |
The Xerophilous species adapt themselves to the basalt and porphyry to some extent, more so than to any other kind of rock except limestone, a circumstance which would lead one to suppose that it is the mechanical, rather than the chemical constitution of the rock, that is influential in attracting them. Besides the four species marked with a star in the preceding list, five others, Anthyllis vulneraria, Astragalus glycyphyllus, Rubus saxatilis, Origanum vulgare, and Polemonium caeruleum, have a fair claim to be regarded as Cheviot plants; and the same is true, even to a still greater extent, with the basalt. The Cheviot heights are much less heathery and more grassy than the sand-stone moors, but they are almost as monotonous from the botanical point of view, and totally destitute, still speaking botanically, of any characteristic features. Take Cheviot itself for an example. Although the hill rises very nearly to 900 yards, and there is a wide extent of surface above 650 yards, we believe the following to be very nearly a complete list of the plants which exceed the latter altitude.
Florula of the Upper Zone on a Porphyritic Hill.
| Ranunculus repens. | Galium saxatile. | |
| Cardamine pratensis. | Saxifraga stellaris. | |
| Sagina procumbens. | Chrysosplenium oppositifolium. | |
| Stellaria uliginosa. | Montia fontana. | |
| Cerastium triviale. | Campanula rotundifolia. | |
| Viola palustris. | Calluna vulgaris. | |
| Rubus chamaemorus. | Vaccinium myrtillus. | |
| Potentilla tormentilla. | vitis-idaea. | |
| Euphrasia officinalis. | Anthoxanthum odoratum. | |
| Empetrum nigrum. | Agrostis vulgaris. | |
| Rumex acetosa. | Poa annua. | |
| Luzula sylvatica. | Festuca ovina. | |
| multiflora. | Nardus stricta. | |
| Eriophorum vaginatum. | Lastrea dilatata. | |
| angustifolium. | Blechnum boreale. | |
| Carex rigida. | Lycopodium selago. | |
| stellulata. | alpinum. | |
| Aira flexuosa. |
We find that several of the common pascual plants do not ascend nearly so high amongst the Cheviots as in the limestone dales. Several instances of this will he noticed in our list of species, of which we may mention here Bunium flexuosum, Heracleum spondylium, Apargia hispida, and Rhinanthus crista-galli, none known on porphyry above 350 yards, but ascending in the limestone dales to 600 or 650 yards. There are a few species which with us are either peculiar to the porphyry and basalt, or more abundant about them than anywhere else. Mr. Tate has mentioned most of them already, and I may add to his list Polemonium cæruleum as peculiar and as preferent, Spergularia rubra, and Filago minima. Of the Flora of our basaltic crags, the following list, which contains all the species noted upon the face, and on the slope, and amongst the debris of the dike, where it stands out conspicuously amongst the low moors west of Kyloe, is a fair illustration.
Florula of a Lower Zone Basaltic Crag.
| Thalictrum flexuosum. | Prunus spinosa. | ||
| Viola sylvatica. | Sedum acre. | ||
| Helianthemum vulgare. | Lonicera periclymenum. | ||
| Ulex europæus. | Hedera helix. | ||
| Spartium scoparium. | Galium cruciatum. | ||
| Lotus corniculatus. | verum. | ||
| Euonymus europæus. | Solidago virgaurea. | ||
| Rosa spinosissima. | Hieracium vulgatum. | ||
| Rubus umbrosus. | Achillea millefolium. | ||
| radula. | Calluna vulgaris. | Erica cinerea. | Convallaria polygonatum. |
| Vaccinium myrtillus. | Triodia decumbens. | ||
| Pyrola media. | Brachypodium sylvaticum. | ||
| Ilex aquifolium. | Agrostis vulgaris. | ||
| Thymus serpyllum. | Festuca ovina. | ||
| Teucrium scorodonia. | Aira caryophyllea. | ||
| Quercus robur. | praecox. | ||
| Juniperus communis. | Pteris aquilina. |
Of the slate rocks we have no large or characteristic development within our bounds, but we have, near at hand, in the Lake district, a very considerable range of hills, where beds of this class cover wide surfaces. Unlike the porphyry and basalt, the slate rocks exclude absolutely the special limestone plants; but like the porphyry and basalt, they are much less heathery than the sandstone, with but little peat upon their surfaces, and with clear transparent streams, and some of the pascual plants do not ascend so high amongst them as with the limestones. But on the other hand, as they rise to a greater height than the hills formed of any of the other three kinds of rock, and present a greater variety of surface in the Upper zone, many plants ascend higher amongst them than anywhere on the east side of the island, and they furnish several boreal plants which we do not get in the east at all. For comparison with the two upper zone florulas already enumerated, we give one for a characteristic crag of the slate formation, and have selected for that purpose a list of species noted on the face of the well-known Striding Edge cliff, which rises from the banks of the Red Tarn, on the west side of Helvellyn, at an elevation above sea level of from 800 to 950 yards.
Florula of an Upper Zone Slate Crag.
| Thalictrum alpinum. | Pyrus aucuparia. | |
| Anemone nemorosa. | Cerastium triviale. | |
| Cardamine pratensis. | Cerastium triviale. | |
| Viola sylvatica. | alpinum. | |
| palustris. | Saxifraga nivalis. | |
| Alchemilla vulgaris, | hypnoides. | |
| alpina. | stellaris. | |
| aizoides. |
| Saxifraga oppositifolium. | Juncus squarrosus. | |
| Oxalis acetosella. | triglumis. | |
| Chrysosplenium oppositifolium. | Carex stellulata. | |
| Galium saxatile. | rigida. | |
| Sedum rhodiola. | Anthoxanthum odoratum. | |
| Sausserea alpina. | Poa annua. | |
| Hieracium chrysanthum. | Festuca ovina. | |
| Campanula rotundifolia. | Aira flexuosa. | |
| Vaccinium myrtillus. | Allosorus crispus. | |
| vitis-idaea. | Lastrea dilatata. | |
| Euphrasia officinalis. | filix-mas. | |
| Thymus serpyllum. | Cystopteris fragilis. | |
| Rumex acetosa. | Lycopodium alpinum. | |
| Oxyria reniformis. | selaginoides. |
The following are the principal species which are conspicuously more frequent amongst the Lake hills than in the east, those marked with a star not being Northumberland, Durham, or North Yorkshire plants at all.
| Nymphaea alba. | Cotyledon umbilicus. | |
| Meconopsis cambrica. | Jasion montana. | |
| *Silene acaulis. | *Lobelia Dortmanna. | |
| *Alchemilla alpina. | Festuca sylvatica. | |
| *Impatiens noli-me-tangere. | *Salix herbacea. | |
| *Circaea alpina. | *Isoetes lacustris. | |
| *Saxifraga oppositifolia. | Allosorus crispus. | |
| Sedum rhodiola. | *Juncus filiformis. | |
| anglicum. | Hypericum androsaemum. | |
| purpureum. |
CHAPTER II.
CLIMATOLOGY, BY JOHN G. BAKER.
Zones of Altitude.—The difference in mean annual temperature between the equator and line of perpetual snow is about 55° Fahrenheit, which is a lowering of rather less than one degree of temperature to a degree of latitude. On the equator at sea-level there is a regular temperature, all the year round, of from 75° to 80° in the shade. An elevation of 100 yards causes, in all latitudes and climates, to speak in round numbers, a lowering of one degree of mean temperature; and for this reason it is often possible, in mountainous intertropical regions, to pass through, in a single day's excursion, a range in temperature equal to that which there is normally between a tropical and arctic station. At the base of the Himalayas, for instance, we may begin the day amongst tree-ferns and palms, climb through a belt of oaks, and chestnuts, and magnolias, and a higher belt of pines and rhododendrons, to a region where no trees can exist, and only mosses, lichens, saxifrages, and gentians grow on the edge of the fields of perpetual snow, and then return again in the evening or next day to the palms and tree-ferns. Even within the compass of Britain we have more than one-third of this whole range of 55°. The difference in mean temperature at sea-level, along the east coast, is not more than 5°; but between the extreme points of the island, say the Lands End and the peak of Ben-na-muic-dhui, the difference is not much under 20°, the mean temperature being 52° for the one station, and not much over freezing-point for the other. In his elaborate work, called Cylele Britannica[5] our principal authority on botanical geography, Mr. H. C. Watson, has divided the surface of the island into two regions of temperature, as modified partly through latitude and partly through altitude, and subdivided each of them into three zones, each of which covers a range of about 3° of mean annual temperature. The upper region he calls the Arctic, and the lower one the Agrarian region, and the boundary between them, which is at an elevation of 600 yards in Wales and the North of England, and descends to 450 yards in the Central Scotch Highlands, is marked by the line of limit of the possible cultivation of grain, which corresponds to the line of upper limit of several familiar wild plants, of which Pteris aquilina, Ranunculus bulbosus, Nasturtium officinale, Lolium perenne, and Geranium molle are examples. The six zones he calls Super, Mid, and Inferarctic, Super, Mid, and Inferagrarian. The Inferagrarian zone embraces all the wide area south of the estuaries of the Dee and Humber, with the exception of some of the Welsh, Cornish, and Devonshire hills. There are a large number of species peculiar to it, of which Clematis vitalba is the most noteworthy. The Midagrarian zone includes the low country in the North of England and southern half of Scotland, and the Superagrarian zone the low ground of the North of Scotland; and both of them belts of corresponding temperature in the hill-country of the more southern latitudes. In some counties, in at least half of the English ones, for instance, we get only one out of these six zones; but there are at least two of them in any county where the hills reach a height of 1000 feet. In our own two counties, beginning to count from below, we get the second, third, and fourth, but not the first, fifth, and sixth. We propose, in the present work, to call these zones which we have simply Lower, Middle, and Upper, and to regard the contour-lines of 300 and 600 yards above sea-level as forming the boundary between them; and these will be the same as Watson's Midagrarian, Superagrarian, and Inferarctic zones.
Mean Temperatures in the Shade.—The following table of mean temperatures is taken from the Reports of the Registrar General, from 1860 to 1864 inclusive. These tables, which are published quarterly by Government, under the editorship of Mr. Glaisher, contain regular observations from a large number of stations scattered up and down the island, and, gathered together, furnish the most complete and reliable data upon its climate which are in existence. Although only four of the stations come within the limits of our field of study, it fortunately chances that these are excellently adapted for showing what we want to know, one of them, North Shields, being on the sea coast; a second, Bywell, inland, in a sheltered position, at a very trifling elevation; a third, Alnwick (the observations are made at High House, 350 feet above sea-level), more northern and exposed; and the fourth, Allenheads (1350 feet above sea-level), being the most elevated locality in Britain where careful thermometric registration has been carried on for any considerable length of time. To these we have added for comparison the figures for York, Greenwich, and Helston during the same period.
- MEAN TEMPERATURES IN THE SHADE.
| Helston. | Greenwich. | York. | Bywell. J. Dawson |
Allenheads. T. Bewick |
N. Shields R. Spence. |
Alnwick. Mr. Scott. | |
| January | 44.1 | 38.4 | 37.3 | 37.3 | 33.1 | 37.2 | 37.5 |
| February | 44.1 | 38.9 | 38.1 | 38.5 | 33.9 | 38.1 | 38.0 |
| March | 45.3 | 41.2 | 39.2 | 39.6 | 34.7 | 38.4 | 39.2 |
| April | 50.9 | 49.5 | 47.9 | 46.6 | 42.1 | 43.9 | 44.9 |
| May | 54.1 | 54.3 | 52.1 | 51.5 | 46.9 | 48.6 | 49.0 |
| June | 57.2 | 58.0 | 56.8 | 55.4 | 51.5 | 52.8 | 52.4 |
| July | 60.6 | 61.4 | 59.8 | 58.4 | 53.7 | 57.2 | 52.4 |
| August | 60.0 | 60.2 | 57.1 | 57.3 | 52.2 | 55.4 | 54.0 |
| September | 58.6 | 58.0 | 54.9 | 55.7 | 50.6 | 53.3 | 52.4 |
| October | 54.1 | 51.2 | 49.1 | 49.2 | 44.2 | 47.3 | 47.4 |
| November | 47.3 | 43.1 | 41.3 | 42.0 | 37.7 | 41.9 | 40.5 |
| December | 46.9 | 41.9 | 41.9 | 42.6 | 37.5 | 41.8 | 41.2 |
| Mean of the Year | 51.9 | 49.7 | 48.0 | 47.8 | 43.2 | 46.3 | 45.7 |
Reckoning by seasons instead of months, taking December, January, and February as winter, and the others in order from this as a starting point, we obtain the following result:—
MEAN TEMPERATURE OF THE FOUR SEASONS.
| Helston. | Greenwich. | York. | Bywell. | Allenheads. | North Shields. | Alnwick. | |
| Winter | 45.0 | 39.4 | 39.1 | 39.5 | 34.8 | 39.0 | 38.9 |
| Spring | 50.1 | 48.3 | 46.4 | 45.9 | 41.2 | 43.6 | 44.4 |
| Summer | 59.3 | 59.9 | 57.9 | 57.0 | 52.5 | 55.1 | 52.9 |
| Autumn | 53.3 | 50.8 | 48.4 | 49.0 | 44.2 | 47.5 | 46.8 |
| Difference between Winter and Sumner | 14.3 | 20.5 | 18.8 | 17.5 | 17.7 | 16.1 | 14.0 |
In the first place, comparing Bywell with Allenheads, we see that the difference, season by season, is 4.7, 4.7, 4.5, and 4.8 for a difference in level of 1300 feet, which quite bears out what we said before, that to speak in round numbers, we may reckon that mean temperature falls as we ascend the hills at the rate of 1° for every 100 yards. For the interior of the country, from London northward to Edinburgh, we may take from 47° to 49° as a fair average, 47° for the South of Scotland, 48° for the North of England, and 49° for the Midland counties: the difference between summer and winter being usually from 18° to 20°. On the sea coast the difference between summer and winter is smaller than in the interior, and the mean temperature generally a shade higher; but in our table this last character, as between By well and Shields, does not hold good. We will take then the annual average of our Lower zone at from 48° to 45°, of the Middle zone at from 45° to 42°, and of the Upper one at 40° or 41°.
The great characteristic of the climate of Britain, as compared with that of other parts of the North Temperate zone, is its equability, the absence of extreme degrees of either heat or cold, and the consequent smallness of the difference there is between winter and summer. We shall see shortly what an important influence this has upon the distribution of plants. Even within the compass of England we can trace palpably the influence of the sea in cutting off the extremes in both directions. Of course, it is on the west side of the island that this influence operates most powerfully, and we see from the table just given, that although Helston is 6° warmer in winter than Greenwich or York, it is rather colder than the former and only 1½° warmer than the latter in summer; at Shields and Alnwick that the difference between summer and winter is only 16° and 14°. The winter is not materially colder at Newcastle than at London; but all the other seasons are, though the difference, when expressed in figures, is probably much smaller than any one who has not studied it as a question of figures will be likely to suppose. The summer is warmer in the interior of the south-east of England than anywhere else in Britain, rising in some places to an average of a little over 60°. The autumn, both in the north and south, comes very near to the average of the whole year, being generally a little above it. But if we turn to the Continent, we shall see how much colder the winters and warmer the summers are in proportion, and how the divergence increases as we pass into the interior. OF MEAN TEMPERATURES OF THE YEAR, AND OF SUMMER AND WINTER, UPON THE CONTINENT.
| LOCALITY. | Average of whole Year. | Summer. | Winter | Difference between Summer and Winter. |
| Umea, Lapland | 35 | 57 | 14 | 41 |
| Stockholm | 42 | 62 | 25 | 37 |
| St. Petersburg | 38½ | 62 | 16 | 46 |
| Moscow | 38½ | 66 | 11 | 55 |
| Copenhagen | 47 | 64 | 31 | 33 |
| Berlin | 47 | 64 | 31 | 33 |
| Hamburgh | 48 | 64 | 32½ | 31½ |
| Warsaw | 48 | 68 | 30 | 38 |
| Paris | 51 | 65 | 38½ | 26½ |
| Vienna | 50 | 68 | 32 | 36 |
| Geneva | 50 | 63 | 35 | 28 |
| Munich | 48 | 65 | 30½ | 34½ |
| Madrid | 59 | 77 | 43½ | 33½ |
| Milan | 55 | 73 | 36 | 37 |
| Naples | 63 | 75 | 50 | 25 |
It is only those parts of Europe that come within the immediate influence of the Mediterranean that have a warmer January than England. With us the mean temperature of the month at sea-level ranges from 32° to 41°. In France the range is almost exactly the same. In some parts of Spain the month reaches 50°; but passing westward from France into the heart of the great mass of the Continent it falls steadily. From the Black Sea to the Baltic it is from 23° to 32°. At Christiania, Stockholm, and Upsala it is 23°. At Moscow, which is in the same parallel of latitude as Edinburgh, it falls to 14°. The difference in position between Edinburgh and Moscow makes a difference in temperature, to the advantage of the former, of 26°. But take July and the difference is all the other way. The average temperature of England in July is from 59° to 63° ; in France it is from 64° to 74° ; in Spain from 68° to 77°; in Central Europe 63° to 72° ; at Stockholm 61°; at Moscow 65°. If we want to match Edinburgh now we shall find a corresponding temperature at Tornea, in Lapland, which is within the Arctic circle, or at Archangel, or at Yakutsk, in Siberia, where the cold in winter is utterly beyond anything of which we here in England can form an idea, the temperature being as far below that of Moscow, not as a figure of speech, but as measured by the thermometer, as that of Moscow is below that of Edinburgh.
Daily Range of Temperature.—We have been speaking so far entirely of what tables of temperature usually deal with, mean temperatures month by month in the shade. We have said nothing at all of the range of temperature during each day, and must next direct our attention to this. The following table, thanks to the very valuable set of observations conducted under Mr. Sopwith's auspices, will tell us substantially all that we need to know here. For By well and Allenheads it gives in the first column the average excess, month by month, of the daily maxima in the sun over those in the shade, in the second the average fall of the nightly minima on the grass below those of the air, in the third the average daily range in the shade; and if we add these three figures together we shall get, in the fourth column, the total daily range to which a plant will be exposed at the surface of the soil, day by day, when it grows in an unsheltered position.
DAILY RANGE OF TEMPERATURE IN SHADE AND EXPOSURE.
| BYWELL, 1857-60. J. DAWSON. |
ALLENHEADS, 1857-60. T. BEWICK. | ||||||||||||||||
| Excess of average daily maxima in sun over those in the shade. | Fall of average daily minima on grass below those of the air. | Average daily range in the shade. | Total average daily range in exposure. | Excess of average daily maxima in sun over those in the shade. | Fall of average daily minima on grass below those of the air. | Average daily range in the shade. | Total average daily range in exposure. | ||||||||||
| January | 3.0 | 6.1 | 10.9 | 20.0 | 3.1 | 1.6 | 9.0 | 13.7 | |||||||||
| February | 7.8 | 7.2 | 12.3 | 27.3 | 7.1 | 2.3 | 9.6 | 19.0 | |||||||||
| March | 13.6 | 6.1 | 12.7 | 32.4 | 15.1 | 1.6 | 10.6 | 27.3 | |||||||||
| April | 23.1 | 7.3 | 15.5 | 45.9 | 20.4 | 3.6 | 12.1 | 36.1 | |||||||||
| May | 17.3 | 7.2 | 13.8 | 38.3 | 30.4 | 3.5 | 16.2 | 50.1 | |||||||||
| June | 21.7 | 7.3 | 14.5 | 43.5 | 28.4 | 3.0 | 15.5 | 46.9 | |||||||||
| July | 22.8 | 8.6 | 14.4 | 45.8 | 24.7 | 5.3 | 14.6 | 44.6 | |||||||||
| August | 20.0 | 9.1 | 14.4 | 44.4 | 25.1 | 4.9 | 13.6 | 43.6 | |||||||||
| September | 17.11 | 9.7 | 14.4 | 41.2 | 21.7 | 6.4 | 13.2 | 41.3 | |||||||||
| October | 6.5 | 7.2 | 12.5 | 26.2 | 15.0 | 3.5 | 10.6 | 29.1 | |||||||||
| November | 4.3 | 6.6 | 12.9 | 23.8 | 6.7 | 2.9 | 9.5 | 19.1 | |||||||||
| December | 5.3 | 6.5 | 23.8 | 23.8 | 0.6 | 1.9 | 9.7 | 12.2 | |||||||||
| 13.6 | 7.4 | 13.4 | 34.4 | 16.6 | 3.4 | 12.0 | 32.0 | ||||||||||
| Winter | 5.4 | 6.6 | 11.7 | 23.7 | 3.6 | 1.9 | 9.4 | 15.0 | |||||||||
| Spring | 18.0 | 6.9 | 14.0 | 38.9 | 22.0 | 2.9 | 13.0 | 37.9 | |||||||||
| Summer | 21.8 | 8.3 | 14.4 | 44.6 | 28.1 | 4.4 | 14.6 | 45.0 | |||||||||
| Autumn | 9.3 | 7.8 | 13.3 | 30.4 | 14.5 | 4.3 | 11.0 | 29.7 | |||||||||
Extreme Degrees of Temperature.—We have spoken as yet altogether of average monthly temperatures, but in connection with our present inquiry, single extreme temperatures, and especially extreme minima, must not be altogether passed over. It will, of course, be gathered, from what has been already said, that extremes in each direction are much smaller in England than on the Continent. The most striking point about the extreme degrees (and this applies particularly to minima) is, how much smaller they are near the sea than in the interior. In England, in very cold weather, the extreme degrees are just as likely to run from north to south as from east to west, so that there is no decided and uniform advantage between say the upper part of the course of the Thames over Tynedale. The part of England which has the decided advantage in this respect is the south-west, and even on the coast the extremes are much smaller on the west than on the east. If we compare an extreme summer with an extreme winter, the result will usually be something like the following:—
MAXIMUM AND MINIMUM TEMPERATURES IN THE SHADE.
| LOCALITY. | Maximum in the month of July, 1859. | Minimum on the night of Dec. 25, 26. 1860. | Difference between the two. |
| Helston | 90 | 32 | 58 |
| Ventnor | 79 | 24 | 55 |
| Greenwich | 93 | 8 | 85 |
| Derby | 83 | 2 | 81 |
| Nottingham | 89.5 | —8 | 97½ |
| Liverpool | 82 | 16 | 66 |
| Manchester | 85 | —3 | 88 |
| Wakefield | 90 | -2 | 92 |
| Leeds | 90 | 6 | 84 |
| York | 82 | —4 | 86 |
| Scarbro' | 77.5 | 16 | 61½ |
| Allenheads | 79 | 8.3 | 70.7 |
| Bywell | 85½ | 3½ | 82 |
| North Shields | 81.4 | 6.8 | 74.6 |
Area of the Zones of Altitude.—Only two of the Cheviot peaks rise distinctly into the Upper zone, Cheviot itself, which reaches within a few feet of 900 yards above sea-level and the neighbouring peak of Hedgehope, which attains nearly 850 yards. Hedgehope is a mere shoulder of hill, but Cheviot has a flat plateau above 800 yards in elevation, which is not less than a mile across from east to west. Besides this, the Upper zone includes the summit of about a dozen of the peaks that encircle the head of the Wear, beginning with Stangend Rigg and Kilhope Law, just above Allenheads, and curving round by way of the county boundary as far east along the watershed between Wear and Tees as Newbiggin and Swinhope. To get into this Upper zone we have always to rise quite out of the ravines, and there is very little rock within its area, so that the range of variation in plant-stations which it furnishes is very small.
The line of limit between the Middle and Lower zones extends up the College Burn to the farm-houses (Goldscleugh and Dunsdale), at the very foot of Cheviot. The Newton Tors rise distinctly into the Middle zone, but Yevering Bell only just reaches it, and what is called Wooler Common, i.e., the portion of the Cheviot range outside the Common Burn, is all below 300 yards. In the Caldgate ravine the Langlee-ford farm-house, at the foot of Hedgehope, is 250 yards above sea-level. From North Middleton Moor the boundary line between the two lower zones stretches along the steep Cheviot slope above Ilderton, Roddam, Alnham, and Biddleston to Alwinton. The highest point of the range of sandstone hills east of the Till is within a few feet of 350 yards, and the moors north of Rothbury, and east of the hollow between Alwinton and Alnham, reach about the same altitude. North of the Coquet there is a wide extent of high undulated moorland, that forms part of the great Cheviot mass, and begins just over Alwinton; but the 300 yards contour line only touches the stream considerably west of Windyhaugh. Between the Coquet and Reedwater the ridge reaches continuously into the Middle zone from the county boundary to Rothbury, a distance of 20 miles. In the wide tract between the Reedwater and South Tyne the area that reaches into the Middle zone is small. North of the North Tyne it includes the ridge along the county boundary from Carter Fell to the moors above Kielder, with spurs towards the south-east; but between the two branches of the Tyne, the country of the Roman wall and the loughs, only a few of the highest ridges and peaks. But south of the South Tyne the hills soon rise to a considerable height. No portion of the main branch within Northumberland is high enough to reach the Middle zone; but the moor between that and the Allen rises into it within a short distance of Haltwhistle and on the other side of the Allen above Catton. The 300 yards contour-line strikes the Allen about 3 miles south of Allentown, and from Catton Moor curves round the head of the Devil's Water along the edge of Slealey Moor to Shotley. South of the Derwent the watershed ridge is Middle zone as far east as Cold Rowley, a distance of 15 miles from the head of the river, and north of the Wear as far east as Wolsingham. The contour line strikes the Wear 15 miles west of this at St. John's Chapel; but on the south of the stream there is again a continuous high ridge, which is Middle zone as far east as Wolsingham, and a short distance beyond Eglestone; and finally, the contour-line strikes the Tees between Wince Bridge and the High Force. The whole area that reaches into the Middle zone is probably not one-twentieth part of the area of the two counties.
Ascending Limits of Wild Plants.—Of the indigenous plants of Britain, 37 per cent, are, to speak in general terms, distributed throughout the length and breadth of the island, whilst 43 per cent, of the species show a decidedly southern tendency, and 17 per cent, are either northern in their tendencies, or at any rate absent from the south and found northward principally amongst the hills. We may safely connect the 43 per cent, with the warmer temperatures, and the 17 per cent, with colder ones, and, of course, such of the former as come within our bounds, are almost all restricted to the low level country. As we ascend from one level to another the number of species decreases rapidly, partly through climate, and partly because at each successive step there is a smaller extent of surface, and the range of variation in station grows rapidly smaller also. If we attribute the running out to climate entirely we shall make a mistake, as we may see by studying the altitudes reached by the same plants in other parts of the island. For instance, with us there are no trees, either wild or planted, above 600 yards, but in Scotland the juniper ascends to 900 yards, the rowan almost as high, the Scotch fir, birch, raspberry, ash, hazel, gale, aspen, Rosa villosa, spinosissima, and several willows, to 500 yards and upwards, 500 yards under the northern latitude being more than equivalent to 600 yards with us. The following table, therefore, must be considered with this qualification. It shows the number of species which we have observed at the different altitudes, and we give also, for each leap of 100 yards up to 600 yards, a list of a dozen common plants which disappear there.
| In Northumberland | and Durham | there are | below 150 | yards | 882 | species |
| " | " | at | 150 | " | 581 | " |
| " | " | at | 200 | " | 541 | " |
| " | " | at | 250 | " | 495 | " |
| " | " | at | 300 | " | 450 | " |
| " | " | at | 350 | " | 407 | " |
| " | " | at | 400 | " | 375 | " |
| " | " | at | 450 | " | 326 | " |
| " | " | at | 500 | " | 300 | " |
| " | " | at | 550 | " | 212 | " |
| " | " | at | 600 | " | 135 | " |
| " | " | at | 650 | " | 108 | " |
| " | " | at | 700 | " | 66 | " |
| " | " | at | 750 | " | 54 | " |
| " | " | at | 800 | " | 34 | " |
| " | " | at | 850 | " | 20 | " |
| Total number of | species | of Lower | zone | ............ | 920 |
| " | " | Middle | " | ............ | 418 |
| " | " | Upper | " | ............ | 108 |
Stop upwards at 100 yards.—Thalictrum flavum, Coronopus Ruellii, Lythrum salicaria, Heliosciadium nodiflorum, Bryonia dioica, Convolvulus arvensis, Nepeta cataria, Ballota nigra, Erythœa centaurium, Tamus communis, Pulicaria dysenterica, Hordeum pratense.
Stop upwards at 200 yards.—Lepidium campestre, Papaver Rhoeas, Barbarea vulgaris, Malva sylvestris, Epilobium hirsutum, Eupatorium cannabinum, Linaria vulgaris, Lamium album, Lithospermum arvense, Rumex conglomeratus, Ophioglossum vulgatum, Trifolium arvense.Stop upwards at 300 yards.—Cardamine amara, Sisymbrium officinale, Viola hirta, Hypericum perforatum, Rubus fruticosus, Geranium dissectum, Trifolium procumbens, T. minus, Arctium lappa, Mentha arvensis, Typha latifolia, Sparganium ramosum.
Stop upwards at 400 yards.—Cerastium glomeratum, Ulex europaeus, Spartium scoparium, Prunus spinosa, Lotus major, Geum urbanum, Galium cruciatum, Fraxinus excelsior, Pyrus malus, Ulmus montana, Viburnum opulus, Quercus robur.
Stop upwards at 500 yards.—Capsella bursa-pastoris, Lonicera periclymenum, Hypericum pulchrum, Prunus padus, Rosa canina, Juniperus communis, Populus tremula, Betula alba, Corylus avellana, Angelica sylvestris, Senecio aquaticus, Taxus baccata, Erica cinerea.
Stop upwards at 600 yards.—Ranunculus flammula, Polygala vulgaris, Stellaria graminea, Oxalis acetosella, Epilobium montanum, Crataegus oxyacantha, Parnassia palustris, Heracleum spondylium, Carduus lanceolatus, Salix caprea, Lastrea filix-mas.
The following is a list of the Northumberland and Durham species, about half the total number, which are northern or montane for Britain as a whole, arranged according to the order in which they are to be met with as we ascend from the low country up amongst the hills.
Below 100 yards.—Thalictrum minus, T. flexuosum, Trollius europaeus, Thlaspi alpestre, Viola lutea, Arenaria verna, Stellaria nemorum, Geranium sylvaticum, Prunus padus, Sanguisorba officinalis, Ribes nigrnm, R. rubrum, R. grossularia, R. alpinum, Sedum villosum, Parnassia palustris, Ligusticum scoticum, Myrrhis odorata, Galium boreale, Crepis paludosa, Carduus heterophyllus, Campanula latifolia, Pyrola minor, Lamium intermedium, Galeopsis versicolor, Mertensia maritima, Pinguicula vulgaris, Primula farinosa, Salix pentandra, S. nigricans, S. laurina, S. phylicifolia, Listera cordata, Cypripedium calceolus, Allium scorodoprasum, Gagea lutea, Blysmus rufus, Scirpus uniglumis, Carex filiformis, Sesleria cœrulea, Melica nutans, Aspidium lonchitis, Equisetum hyemale, E. umbrosum, Lycopodium selaginoides, Elymus arenarius.
At 100 yards.—Drosera anglica, Callitriche autumnalis, Hieracium argenteum, H. crocatum, H. prenanthoides, Sagina subulata, Gnaphalium dioicum, Andromeda polifolia, Pyrola media, Empetrum nigrum, Carex dioica, C. limosa, Polypodium phegopteris, P. dryopteris.
At 150 yards.—Potentilla alpestris, Saxifraga aizoides, S. stellaris, Meum athamanticum, Galium sylvestre, Crepis succisœfolia, Hieracium pallidum, H. cœsium, H. gothicum, H. corymbosum, Vaccinium vitis-idœa, V. uliginosum, Trientalis europœa, Rumex aquaticus, Habenaria albida, Carex pauciflora, C. irrigua, Allosorus crispus, Asplenium viride, A. germanicum, A. septentrionale, Equisetum variegatum.
At 200 yards.—Saxifraga hypnoides, Linnœa lorealis, Hieracium lasiophyllum, Arbutus uva-ursi, Pyrola secunda, Polemonium cœruleum, Convallaria verticillata, Festuca sylvatica.
At 250 yards.—Potentilla fruticosa, Polygonum viriparum.
At 300 yards.—Thalictrum alpinum, Cornus suecica, Hieracium anglicum, H. iricum, Melampyrum sylvaticum, Lycopodium alpinum.
At 350 yards.—Gentiana verna, Bartsia alpina.
At 400 yards.—Sedum rhodiola, Saxifraga hirculus, Tofieldia palustris, Carex capillaris.
At 450 yards.—Draba incana, Woodsia ilvensis.
At 500 yards.—Rubus chamœmorus, Epilobium anagallidifolium, Juncus triglumis.
At 550 yards.—Carex rigida.
The Climate as tested by cultivated Plants.—The following paragraph, from Winch's Essay,[7] will convey as good an idea as we can give of the power of the heat in summer. "Seven different species of fruit-trees ripen their fruit in the southern counties, which seldom do so in this latitude: these are the vine, the fig, the quince, the medlar, the walnut, the chestnut, and the mulberry. This may be ascribed, in some measure, to the presence of cold easterly winds during the spring months, destroying the blossoms; to the low temperature of our autumns, which prevents the young wood from hardening and maturing the buds enveloping the flowers in embryo; but more especially to the want of a continuance of sufficient heat, during the summer, to bring the fruit which is occasionally formed to perfection, for all these trees withstand the winter frost tolerably well in sheltered situations. The vine seldom flowers, and if by chance small grapes are produced, they soon drop off. The fig is seldom seen out of the hot-house, or against a hot wall, and is otherwise barren, except in the south-eastern corner of Durham; and speaking generally, the same may be said of the quince and medlar. These flower freely, and the latter has ripened its fruit twice during twenty years at Jesmond, near Newcastle. The walnut and chestnut stand in the same predicament; and even the filbert bears very sparingly. The mulberry is here a low stunted tree, but in hot summers bears abundance of small fruit, which in part comes to maturity, and is well flavoured."
Respecting the shrubs liable to be killed by frost in severe winters we need not say much, as the species are very much the same everywhere, along the east side of the island, between Edinburgh and London. The following are some of the commonest, those placed early in the list being the most liable to suffer. For fuller detail bearing upon this point, and facts, showing how some of them, in cases of severe frost, have stood better in the immediate vicinity of the sea, and in slightly elevated localities, than in low-lying inland stations, we may refer our readers to two papers, by Ralph Carr, Esq., in the third and fifth volumes of our Transactions.
Laurus nobilis, Cedrus Deodara, Viburnum tinus, Cryptomeria japonica, Rhamnus alaternus, Quercus ilex, Phillyrea latifolia, media, angustifolia, Cistus ladaniferus, Thuia filiformis, Aucuba japonica, Prunus lauro-cerasus, P. lusitanica, Arbutus unedo, Ilex aquifolium, Ulex europaeus, Spartium scoparium.
To the upper limits in Northumberland and Durham of the various cultivated plants we have paid special attention, because it seems likely that many of them are grown successfully with us under lower temperatures than they are anywhere else in the island. There is a great contrast in the height to which houses and cultivation reach between the Cheviots and the Durham and South Tynedale hills, owing, no doubt, to the broad open dales and more gradual slopes of the latter, and the attraction of their mineral treasures. In the whole Cheviot tract there are probably not more than a dozen farm houses at above 1000 feet, and the cultivation of grain stops at 200 or 250 yards. In Durham, the highest regularly-inhabited house which we have seen, is the farm-house of Grasshill, on the west of the peak of Highfield, which is just 2000 feet above sea-level. In West Allendale there is a small village, called Coal Cleugh, at from 1650 to 1700 feet; and in East Allendale some of the farm houses are nearly as high, and the considerable village of Allenheads, with a church, school house, mining office, and gentleman's hall and grounds, stands at a height of from 1300 to 1400 feet. The following is a list made during various visits to Teesdale, of the height at which the different trees grow, either in a wild or planted state, and to which the different kinds of grain and vegetables are cultivated.
At 2000 feet.—Rhubarb, potatoes, turnip. A crop of each of these grown by the Highfield farmer in the hollow of a disused limekiln.
At 1700 feet.—Salix caprea.
At 1650 feet.—Rubus idaeus, Pyrus aucuparia, Corylus avellana, Salix aurita, S. phylicifolia, Rosa tomentosa, Ribes rubrum, R. grossularia (fruit poor).
At 1600 feet.—Oak, beech, spruce, sycamore, hawthorn, Wych elm, larch, Scotch fir. At 1500 feet.—Juniper, Prunus padus, Rosa canina, Salix fusca, honeysuckle, aspen, Mentha viridis, gooseberry (fruit good).
At 1450 feet.—Rosa spinosissima.
At 1250 feet.—Apple, pear (planted eight years, flowers, but has not fruited), cabbage, potato field, spinach, Ribes nigrum, clover field, Sinapis alba, bean, radish, chives, carrot, lettuce, Mentha gentilis.
At 1100 feet.—Ivy.
At 1050 feet.—Viburnum opulus, Rubus suberectus, alder, strawberry, onion, leek, horse-radish, peas.
In Weardale our highest measurements for the cereals are—oats, 1340 feet; barley, 1000 feet; wheat, 750 feet; in Allendale, oats, 1600 feet; barley, 950 feet; wheat, 800 feet. In making a similar list to the above for Allendale, we had the kind and efficient help of Mr. Ralph Murray, of Allenheads, who spent, when we were staying at the village, in 1865, a considerable time in traversing with us Mr. Beaumont's extensive gardens and plantations, for the purpose of compiling it. Our first list is of the species noticed in the gardens at Coal Clough (1650—1700 feet), in West Allendale; and of Gill's House (1665 feet), and Shorngate House (1640 feet), in East Allendale, say, in round numbers, of species grown at 550 yards—
Fruits.—Plum, raspberry, red currant, black currant, Rubus saxatilis.
Vegetables.—Potato, rhubarb, turnip, cabbage, Mentha viridis, M. gentilis, Anthemis nolilis, wormwood, lettuce, carrot, cauliflower, Tropaeolum, marjoram, onion.
Trees and Shrubs.—Sycamore, ash, larch, hawthorn, spruce, Scotch fir, Wych elm, Syringa vulgaris, Salix viminalis, S. purpurea, S. Smithiana, S. phylicifolia, Rosa alba. Our next list relates to Mr. Beaumont's grounds, which are at an altitude of from 1370 to 1460 feet, facing the north, and cut off from the south by a ridge of high moorland.
Fruits ripen.—Strawberry, apple, peach, pear, cherry, plum, red currant, black currant, rasp, gooseberry.
Yegetables.—Peas, beans, asparagus, beet, sea kale (Crambe), broccoli, Brussels sprouts, cabbage, carrot, cauliflower, cress (Lepidium sativum), garlic, leek, lettuce, Sinapis alba, onion, parsley, parsnip, rhubarb, radish, rampion, salsafy, spinach, turnip, vegetable marrow, potato, basil, fennel, hyssop, lavender, marjoram, thyme, balm, sage.
Trees (have all lasted through several winters, but many not flowered.)—Alder, ash, beech, birch, horse chestnut, Wych elm, Balm of Gilead fir, black, white, and red American spruce, Scotch fir, silver fir, Pinus austriaca, Cembra and laricio, mountain ash, hazel, holly, hornbeam, laburnum, larch, Acer campestre, Populus alba, nigra, dilatata, common oak, Turkey oak, sycamore, Pyrus Aria, black thorn, hawthorn, walnut, Salix fragilis, viminalis, Smithiana, pupurea.
Ornamental Shrubs.—Sweet briar, Berberis vulgaris, Mahonia aquifolium, Thuja occidentalis, Ribes sanguineum, box, Cornus sanguinea, Viburnum opulus, Lonicera caprifolium, Prunus lusitanica, P. lauro-cerasus, holly, Kerria japonica, mezereon, lilac, privet, Wellingtonia, snowberry, Irish and common yew, white and yellow broom, ivy, juniper, Azaleas (pontica, &c), rhododendrons, roses (alba, &c).
Rainfall.—Of the six hundred and six British plants with a southern tendency, we find that one hundred and twenty-seven show a decided preference for the east, and seventy for the west side of the island, and this no doubt is principally to be explained by the fact that the former is drier, both above and below the surface of the earth. But, as the distribution of the rainfall through our province cannot be traced to have any appreciable influence on the distribution of its plants, we will content ourselves with quoting here the figures for the various stations as they stand in the last Club report. The stations for which no altitude is given are very little above sea level.
| PLACE. | Altitude in feet. | Number of years observed. | Annual rainfall in inches. |
| Darlington | 140 | 2 | 20.7 |
| Whorlton | 450 | 2 | 25.3 |
| Wallsend | … | 6 | 27.0 |
| Wylam | 96 | 11 | 27.7 |
| Stamfordham | 400 | 9 | 29.1 |
| Bywell | 87 | 9 | 28.0 |
| Allenkeads | 1360 | 9 | 46.9 |
| Park End, North Tyne | 277 | 10 | 32.3 |
| Glanton, foot of Cheviot | 534 | 10 | 27.6 |
| Cresswell | … | 9 | 22.4 |
| Sunderland | … | 8 | 21.4 |
This is just as might be expected, the minimum along the coast, and the quantity growing gradually greater inland to the maximum in the vicinity of the western ridges.
Wind.—We ought not to pass entirely unnoticed the influence which the force of the wind has upon vegetation. Take a maritime station, like Shields, for instance, and compare it with a sheltered inland locality like Bywell, and it is probable that the force of the wind, as measured by an anemometer, is twice as great on the average of the whole year at the former place as at the latter. The consequence is, that along the whole coast, exposed as it is to the full force of the cold breezes of the east, trees of any kind can attain to a moderate height and luxuriance only in sheltered situations; and no doubt, the same reason causes our springs to be later, and our climate to be more unfavourable for herbaceous plants that love warmth and shelter, in comparison with Yorkshire and the Midland Counties, than the mere figures of temperature indicate. We shall have occasion, in another part of the work, to point out how rapidly, in Northumberland and Durham, the characteristically southern plants thin out. CHAPTER III.
PHYSICAL GEOGRAPHY, BY J. G. BAKER.
Under this head we propose to go through, one by one, the districts founded upon the river-drainage as they stand in the map, and to attempt to describe briefly the most salient features of their physical geography. It is not without considerable hesitation that we lay before the members of the Club a summary of the notes which we have had, from time to time, the opportunity of making upon this head, hesitation arising from the feeling that a large proportion of them are better acquainted with the country about which we are writing than we are ourselves. But we hold strongly to the opinion that it adds very much to the interest and value of a local Flora, that the physical characters of the tract of country to which it relates should be explained, side by side with the enumeration of the plants; and we expect, of course, that this paper will meet the eyes of many to whom our wide sweeps of moor, lowland denes, streams and fields, and long line of craggy coast are ideals unrealized, and we trust also that it may help to recall pleasant memories of bygone excursions in the minds of those to whom these are amongst things familiar.
The total area of Northumberland is 1952 square miles. Its greatest length, from north to south, is 60 miles; its breadth, from Tynemouth to the Irthing, 54 miles; but in the northern part, opposite Wooler, not more than 24 miles. The area of Durham is 973 square miles; its greatest length 48 miles, and its breadth 39 miles. The total area of the two is 2925 square miles, which is about one-seventeenth of England exclusive of Wales, and one-thirtieth of Britain, exclusive of Ireland.
The towns of Northumberland are twelve in number—in the first rank Newcastle, then North Shields and Tynemouth, to all intents one, then the three old centres of feudal times, Alnwick, Morpeth, and Hexham; the others, Allenton, Belford, Bellingham, Haltwhistle, Rothbury, and Wooler, small country towns, of an almost entirely agricultural character. The towns of Durham are thirteen—Durham, Bishop Auckland, Barnard Castle, Darlington, Gateshead, Hartlepool, Stockton, Sunderland, South Shields, Sedgfield, Stanhope, Staindrop, and Wokingham. As the map will show, we have traced out eleven drainage districts, the first four of which correspond to the Cheviot-land vice-county[8] of Watson's Cybele Britannica, the second four to his southern division of Northumberland, which we may call Tyne-land, and the last three to the county of Durham. In round numbers we may say the area of Cheviot-land is 800 square miles, of Tyneland 1150 square miles, and of Durham 950 square miles; and we would ask the special attention of our readers to these vice-counties, as we intend to give a separate list of the plants of each, or, to speak more accurately, to give, under each species, the initial letter C, N, and D of the vice-counties in which it grows. The districts which we have defined are as follows:—
1. Cheviot-land vice-county.
1. Tweed and Till district.
2. North-eastern district.
3. Aln district.
4. Coquet district.
2.Tyne-land vice-county.
5. Wansbeck district.
6. North Tyne district.
7. South Tyne and Allen district.
8. South-eastern district.
3. Durham (vice) county.
9. Derwent district.
10. Wear district.
11. Tees district.
We give, in the first place, a table, showing the distribution of the one hundred and eight boreal species through the eleven drainage districts.
| Thalictrum alpinum | … | … | … | … | … | … | … | … | … | … | 11 |
| minus | 1 | 2 | 3 | 4 | 5 | … | … | 8 | 9 | 10 | 11 |
| flexuosum | 1 | 2 | … | … | … | … | … | … | … | … | 11 |
| Trollius europaeus | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Thlaspi alpestre | … | … | … | … | … | … | 7 | … | … | 10 | 11 |
| Draba incana | … | … | … | … | … | … | … | … | … | 10 | 11 |
| Viola lutea | 1 | … | … | 4 | … | 6 | 7 | … | 9 | 10 | 11 |
| Drosera anglica | … | … | … | … | … | … | 7 | 8 | … | … | … |
| Sagina subulata | … | 2 | 3 | … | … | … | … | … | … | … | … |
| Arenaria verna | … | 2 | … | … | … | … | 7 | … | 9 | 10 | 11 |
| Stellaria nemorum | 1 | … | 3 | 4 | … | 6 | … | 8 | 9 | 10 | 11 |
| Geranium sylvaticum | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Potentilla fruticosa | … | … | … | … | … | … | … | … | … | … | 11 |
| alpestris | … | 2 | … | … | … | … | … | … | … | … | 11 |
| Rubus chamæmorus | 1 | … | … | 4 | … | 6 | 7 | … | 9 | 10 | 11 |
| saxatilis | 1 | … | 3 | … | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Sanguisorba officinalis | … | … | … | … | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Epilobium anagallidifolium | 1 | … | … | … | … | … | … | … | … | … | 11 |
| Epilobium alsinifolium | 1 | … | … | … | … | … | … | … | … | 10 | 11 |
| Callitriche autumnalis | … | … | … | … | … | … | … | 8 | … | … | … |
| Ribes petræum | … | … | … | … | … | … | 7 | 8 | 9 | … | 11 |
| Sedum rhodiola | 1 | … | … | … | … | … | … | … | … | … | … |
| Sedum villosum | 1 | 2 | 3 | 4 | 5 | … | 7 | … | … | 10 | 11 |
| Saxifraga stellaris | 1 | … | 3 | 4 | … | … | 7 | … | 9 | 10 | 11 |
| aizoides | … | … | … | … | … | … | 7 | … | … | … | 11 |
| hirculus | … | … | … | … | … | … | … | … | … | 10 | … |
| hypnoides | 1 | … | … | … | … | … | … | … | … | … | 11 |
| Parnassia palustris | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Cornus suecica | 1 | … | 3 | … | … | … | … | … | … | … | … |
| Ligusticum scoticum | … | 2 | … | … | … | … | … | … | … | … | … |
| Meum athamanticum | … | … | … | … | 5 | … | … | … | … | … | … |
| Myrrhis odorata | 1 | … | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Linnæa borealis | … | … | … | … | 5 | … | … | … | … | … | … |
| Galium sylvestre | … | … | … | 4 | … | … | … | … | … | 10 | 11 |
| boreale | 1 | … | … | … | … | 6 | 7 | 8 | … | … | 11 |
| Crepis succisæfolia | 1 | 2 | 3 | 4 | 5 | 6 | 7 | … | … | 10 | 11 |
| paludosa | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Hieracium anglicum | … | … | … | … | … | … | … | … | … | … | 11 |
| iricum | … | … | … | … | … | … | … | … | … | … | 11 |
| argenteum | 1 | … | … | 4 | … | … | … | … | … | … | … |
| pallidum | 1 | 2 | … | … | … | … | … | … | … | 10 | 11 |
| lasiophyllum | … | … | … | 4 | … | … | … | … | … | … | … |
| cæsium | … | 2 | … | 4 | … | … | … | … | … | … | 11 |
| gothicum | … | … | … | 4 | … | 6 | 7 | … | 9 | 10 | 11 |
| prenanthoides | 1 | … | … | 4 | … | 6 | 7 | … | … | … | … |
| crocatum | 1 | … | … | … | … | 6 | … | … | … | 10 | 11 |
| corymbosum | … | … | … | 4 | … | 6 | … | … | … | … | 11 |
| Carduus heterophyllus | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Gnaphalium dioicum | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Campanula latifolia | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Andromeda polifolia | … | … | … | … | 5 | 6 | … | 8 | … | … | … |
| Arbutus uva-ursi | … | … | … | … | … | … | 7 | 8 | … | … | 11 |
| Vaccinium vitis-idæa | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| uliginosum | … | … | … | … | … | … | 7 | … | … | … | 11 |
| Pyrola media | … | 2 | 3 | … | 5 | … | … | 8 | 9 | 10 | … |
| minor | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| secunda | 1 | … | … | … | … | … | … | … | … | … | … |
| Gentiana verna | … | … | … | … | … | … | … | … | … | … | 11 |
| Polemonium coeruleum | … | … | … | 4 | … | … | … | … | … | … | … |
| Bartsia alpina | … | … | … | … | … | … | 7 | … | … | … | 11 |
| Melampyrum sylvaticum | 1 | … | … | 4 | … | … | … | … | … | … | … |
| Primula farinosa | … | … | … | … | 5 | … | 7 | 8 | 9 | 10 | 11 |
| Trientalis europaea | 1 | 2 | 3 | 4 | 5 | … | 7 | … | 9 | 10 | … |
| Polygonum viviparum | … | … | … | … | … | … | … | … | … | 10 | 11 |
| Rumex aquaticus | … | … | … | 4 | … | … | 7 | … | … | 10 | 11 |
| Empetrum nigrum | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Salix pentandra | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| nigricans | 1 | … | … | 4 | … | 6 | 7 | 8 | 9 | 10 | 11 |
| laurina | 1 | … | … | … | 5 | … | … | … | 9 | … | … |
| phylicifolia | … | … | … | … | … | … | 7 | 8 | 9 | 10 | 11 |
| Habenaria albida | … | … | … | … | 5 | 6 | 7 | … | 9 | … | 11 |
| Gagea lutea | … | 2 | 3 | … | 5 | 6 | 7 | … | … | 10 | 11 |
| Convallaria verticillata | … | … | … | … | … | … | 7 | … | … | … | … |
| Tofieldea palustris | … | … | … | … | … | … | … | … | … | … | 11 |
| Juncus triglumis | … | … | … | … | … | … | … | … | … | … | 11 |
| Blysmus rufus | … | 2 | 3 | … | … | … | … | … | … | 10 | … |
| Scirpus uniglumis | … | 2 | … | … | … | … | … | 8 | … | … | … |
| Elyna caricina | … | … | … | … | … | … | … | … | … | … | 11 |
| Carex dioica | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| pauciflora | … | … | … | … | … | 6 | … | … | … | … | … |
| rigida | 1 | … | … | … | … | … | … | … | … | … | 11 |
| capillaris | … | … | … | … | … | … | … | … | … | … | 11 |
| limosa | 1 | 2 | … | … | 5 | … | 7 | … | … | … | … |
| irrigua | … | … | … | … | … | … | 7 | … | … | … | … |
| filiformis | … | 2 | … | … | … | … | 7 | … | … | … | … |
| Sesleria caerulea | … | … | 3 | … | … | … | … | … | 9 | 10 | 11 |
| Melica nutans | … | … | … | … | … | 6 | 7 | … | … | 10 | 11 |
| Festuca sylvatica | … | … | … | … | … | … | … | … | … | 10 | … |
| Elymus arenarius | … | … | 3 | 4 | … | … | … | 8 | 9 | 10 | 11 |
| Woodsia ilvensis | … | … | … | … | … | … | … | … | … | … | 11 |
| Polypodium phegopteris | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Allosorus crispus | 1 | … | 3 | … | 5 | 6 | 7 | … | … | 10 | 11 |
| Asplenium septentrionale | … | 2 | … | … | … | … | … | … | … | … | … |
| germanicum | … | 2 | … | … | … | … | … | … | … | … | … |
| viride | 1 | … | … | … | … | … | 7 | … | … | 10 | 11 |
| Lycopodium alpinum | 1 | … | … | … | … | … | 7 | … | … | 10 | 11 |
| selago | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| selaginoides | 1 | 2 | 3 | 4 | 5 | … | 7 | 8 | 9 | 10 | 11 |
| Equisetum umbrosum | … | … | … | 4 | … | … | … | … | … | … | 11 |
| hyemale | … | … | 3 | 4 | 5 | … | … | 8 | 9 | 10 | … |
| variegatum | … | … | … | … | … | … | 7 | … | … | … | 11 |
| Total | 48 | 34 | 34 | 40 | 35 | 34 | 51 | 36 | 38 | 54 | 74 |
The result which, we obtain from this list is not the less interesting from being scarcely that which we should, a priori, have expected. The greatest concentration of these boreal plants is, we see, in the most southern of the districts. The special richness of Teesdale in Montane species is a fact which we cannot undertake to explain; but if the relative abundance with which these plants occur in the different districts were to be taken into consideration, the contrast would be much more striking than it is now. The small proportion of the total number of species which any other district, except that of the Tees, yields is noteworthy, especially the lowness of the figure for district number one, which, besides being the most northern in position, contains the high Cheviot peaks, and a wide area of elevated ground. We may take the even distribution of a considerable number of these plants through the districts as indicating (what is a characteristic feature of the physical geography of the two counties) the large extent of surface which is occupied by low hilly country, a circumstance which explains also a point upon which we shall afterwards have occasion to dwell, and the large number of plants common in the south and centre of England that come to a stop in their wanderings towards the north within our bounds. So much premised by way of introduction, we will now take the districts seriatim.
1. TWEED AND TILL DISTRICT.
The Tweed altogether drains an area of 1870 square miles, including nearly the whole of Roxburghshire, Berwickshire, Peeblesshire, and Selkirkshire, and portions of Haddingtonshire, Edinburghshire, Lanarkshire, and Northumberland. At the town of Peebles, 50 miles from the coast in a direct line, it is only 500 feet above sea-level in altitude. For about 18 miles in a direct line the main branch forms the northern boundary of Northumberland, a broad sinuous stream, flowing more rapidly than is usual with rivers of so large a size, past Carham, Cornhill, Tillmouth, Twizell, and the ruined castle of Norham to Berwick. The banks are in some places level and grassy, but sometimes steep and wooded. The influence of the tide reaches up to Norham, which is 10 miles inland. There is a small burn at Learmouth, and a swamp in the level country, which yields Lastrea thelypteris, Cladium mariscus, Cicuta virosa, and Carex limosa. Along the whole course of the main stream, on the southern side, the elevation is under 300 feet, and the country well-cultivated and fertile. The Till in its lower part is about midway between the sea and the western border, and nearly parallel with both, a sluggish stream of considerable size, winding lazily amongst the meadows and corn-fields, overhung by willows and alders, with neighbouring swamps full of Equisetum limosum, Sparganium, Iris, and Carex vesicaria. This is the character of the stream for nearly 20 miles. From this cultivated flat on the west the Cheviot mass rises up abruptly, and on the east the sandstone range rises up, also with considerable abruptness, to shelter it from the sea breezes, moor-like above and the flank wooded past Eglingham, Bewick, and Chillingham, but becoming lower and greener at Doddington and Lowick, and, still further northward, becoming gradually almost lost in the level country as it nears the Tweed. Titlington Pike, the highest point of this range above Eglingham, is 765 feet in elevation; Ross Castle, the highest peak of the whole range, a heather-clad height above the pleasant park of Chillingham, which stands out conspicuously in all the Cheviot views, is 1036 feet. Black Heddon, a few miles further north, is 646 feet; but the stream from the west side of this runs down into the sea direct, not into the Till. The village of Lowick, which is just upon the watershed midway between Wooler and Berwick, is not more than 400 feet in elevation. The multiplicity of names for the streams in this region puzzles a stranger. The Bremish is only another name for the main Till stream before it emerges from the hills. This main branch rises in the very heart of the Cheviot mass, close upon the county boundary. The upper part is shut in between two huge masses of hill, Cheviot itself rising to a height of 2676 feet upon the north, and Weather Cairn and Cushat Law on the south to 1836 feet and 2019 feet. From the hanging stone at the south-east corner of Cheviot, a spur of high hill runs nearly 10 miles due east parallel with the Breamish over Hartside and Reveley. The principal farm-houses of the upper part of the stream are called Bleakhope and Shillmoor. Due south of the peak of Hedgehope, on a little side-stream from this northern ridge, is Linhope Spout, the finest waterfall of the district. High up on the bare hill-side, 500 feet above Reveley, the waters of this little burn fall over a brown porphyritic crag 50 feet in depth into a deep basin, and as the directories tell us, "the cataract is sometimes called the Roughton Linn, from the great noise made by the fall of the water when the stream is full." Where the road from Branton to Wooler crosses it, this northern spur is only 550 feet in elevation. A lower ridge of hill than that of which we have been speaking runs between the Breamish and the head of the Aln. The peaks between Alnham and Ingram are Cochrane Pike (1096 feet) and the Grey Yade of Coppal (900 feet); and the highest point of the road west of Glanton is 500 feet. At Branton, where this main stream enters the flat cultivated country, the character of these Cheviot rivulets, in their short stage of transition from hill-burns to low-country streams, is well shown. They spread out into broad shallow channels, with beds full of pebbles and rounded boulders of porphyritic rock, with wild roses, broom, furze, and bushes of Salix purpurea scattered over the flat and dry-loving plants amongst their sandy borders, Galium verum, lotus, harebell, Anthyllis, Reseda luteola, and Malva moschata, and in the thin bare places Trifolium arvense, Filago minima, and Aira caryophyllea. Opposite Eglingham the distance from the hill-spur on the north to that on the south is not more than 2 miles. South of the Reveley ridge, on the east slope of Hedgehope, is a depression in the Cheviot mass, down which two small streams, Roddam burn and Lilburn, run down to join the Till, the former with a pleasant wooded dene. From the sandstone ridge there are no streams of any consequence entering the Till south of Chatton, where it turns more to the west, till it receives the branch which is called sometimes the Caldgate Burn and sometimes the Wooler Water. The town of Wooler is situated on the very outskirts of the Cheviot mass on a rather steep slope, the main street being about 300 feet above sea-level and the bridge 50 feet lower. The highest mass of hill, to which the name of Cheviot especially belongs, is most easily reached from the town by following the high-road up the Wooler Water to Langlee-ford, by way of Earl, a distance of 5 miles. The high ridge is about a mile long, the western end, round what is called the Dunsdale Cairn, a peaty swamp, the slightly higher eastern cairn drier. The Wooler Water rises on the back of this ridge in a depression which runs south of the ridge over into Henhole. Two miles above Langlee-ford there is a small waterfall called Hartside Linn, above which the ravine is bare and monotonous. The highest points of Cheviot and Hedgehope are not more than 2 miles apart, and the steepness of the ravine which separates them may be best understood from the fact that the Langlee-ford farm-house, which is nearly in a direct line between the two peaks, is 1600 feet in level below the one, and nearly 1900 feet below the other. But there is very little crag upon the sides of this ravine, and very soon after leaving the house in climbing upwards we pass out into open moory ground, leaving all trees and enclosures behind. We could only see thirty-five plants upon the hill at an elevation of upwards of 2000 feet, and of these we have already given a list. The Langlee-ford farm-house is 400 feet above Wooler, 750 feet above sea-level. For 3 miles below it the stream runs down a fine ravine, from which the hills rise sharply to a height of from 1500 feet to 1000 feet above it on both sides, the lower part of their sides being somewhat wooded, the trees being principally birch, oak, rowan, and hawthorn, and the flat one continuous alder-grove. Over the ridge on the east of the stream the level declines directly towards Roddam and Ilderton. The hill just above Langlee-ford is crowned by a craggy crest (Langlee Crags), and the flanks of this lower part of the ravine are frequently covered with loose rocks. These faces of hill, or rather the heaps of loose porphyritic boulders that cover them, are characteristic of the district. From the south-west side of this glen it is several miles across to the series of rounded bell-shaped "tors" that form the southern flank of the range above Yevering and Akeld, and the intervening space is filled up by a heathery plateau, which is considerably lower in level than the tors which girdle it. Right through the heart of this plateau, from west to east, to join the Wooler Water a little above Earl, flows a stream which is called the Common Burn, with a fork on the north called Broadstruther Burn. Both are bare moorland rivulets till they unite, after which the banks are wooded, and there is a narrow craggy ravine with a waterfall at the bottom, about which grow Hieracium prenanthoides and Crepis succisaefolia. But the most interesting glens of the Cheviot, whether for the botanist or lover of scenery, are those which penetrate the great ridge on the north, and contain the sykes which unite to form the College Burn. Within less than a mile from the cairn these decline in level 1600 feet, steep, bare, treeless ravines, their rivulets fed from innumerable bright-green well-heads, where copious fountains gush clear and cool out of the hill-side, flanked by embankments of loose stones or precipitous columns of red or grey porphyritic crag, the stream at the bottom leaping from terrace to terrace down a channel so steep that it is almost one continuous waterfall in the rainy season. To reach these from Wooler the best way is not to take the Earl road at all, but that which leads out of the head of the town on the west, and follow a foot-path across the central heathery plateau, the portion of which nearest the town is called Wooler Common, crossing the Common Burn where the two branches join, and following the Broadstruther Fork out to its head. There is a horse-track all the way, that leads into the hollow of the College Burn, which is an open grassy depression of no particular interest, except that just above its very head, in the direction of the highest Cheviot cairn, is the station for Cornus suecica. The highest farm-house on the College is called Goldscleugh, and is a little over 1000 feet in altitude. There is a small ravine above it, but the three principal ones are further west. From the next farm-house, about half a mile lower down, we can look right, up two of the rocky ravines, one of which, called Dunsdale, originates in the east, and the other, called the Brizzle or Bizzle, on the west of the western Cheviot cairn. On the flank of this ridge, from 1200 feet down to the stream, we have one of the few relics of the primeval forest of Cheviot, consisting here almost altogether of birch. To reach Henhole, which is perhaps the finest, or at any rate the rockiest glen of the three, from Dunsdale, the ridge on the west has to be crossed, as the glen sweeps round the west end of the highest ridge so as almost to join the Langlee glen at its head. Of the well-heads of the upper part of these ravines, from 1500 to 1800 feet, the following are the principal plants:—
| Caltha palustris. | Lychnis flos-cuculi. | |
| Sedum villosum. | Taraxacum palustre. | |
| Saxifraga stellaris. | Carduus palustris. | |
| Epilobium obscurum. | Galium palustre. | |
| alsinifolium. | Juncus effusus. | |
| Myosotis repens. | lamprocarpus. | |
| Montia fontana. | Carex pulicaris. | |
| Stellaria uliginosa. | panicea. | |
| Pamassia palustris. | vulgaris. |
Amongst the debris there is abundance of Allosorus crispus, but the only other rare fern, Asplenium viride, is more difficult to find. The more note-worthy montane plants of the crags are—Sedum rhodiola, Hieracium argenteum and pallidum, Rubus saxatilis, Poa Balfourii, Saxifraga hypnoides, and Epilobium angustifolium. The streams of these ravines join at Southernknow, 3 miles below which is the finest of the low-level Cheviot water-falls, Heathpool Linn. On the south is a dry bell-shaped hill, 1700 feet in altitude, and on the north a porphyritic crag sweeps down suddenly into the stream, contracting it for a space of 30 or 40 yards into a narrow rocky channel. The rocky banks are overgrown by bright-green shade-loving mosses, and over-shadowed by ash and elm; and a natural wood of oak, rowan, and birch extends along the slope of the southern hill. Here grow Dianthus deltoides, Euonymus europaeus, Poa nemoralis, Epilobium angustifolium, Hieracium argenteum and crocatum. At Kirk-Newton the Glen is joined by the Beaumont, which rises on the Scotch side of the Cheviot mass, and sweeps round it in a curve past Yetholm and Mindrum. The Kilham Hills, which are enclosed in the angle between the two streams, are a series of rounded tors not exceeding 1000 feet in height, dry, and not interesting botanically. From Heathpool to Wooler, some 5 miles, the north flank of the Cheviot mass is guarded by the series of bell-shaped hills to which we have previously referred. In order, from west to east, they are called Newton West Tor (1762 feet), Newton East Tor, Yevering Bell (1182 feet), Akeld Hill, and Humbledon Heugh (977 feet). At their base the country is almost a dead flat, so that they are conspicuous from a great distance and command an extensive view, north-eastward to St. Abb's Head and the Berwickshire hills, northward to the Lammermuirs,. westward up the Tweed Yalley, past the Eildons, to the loftier hills round the head of Ettrick, Liddesdale, and Teviotdale. The Caldgate stream joins the Till within a mile of Wooler. At Doddington the latter receives a rivulet, called Hetton Burn, from the sandstone ridge on the west, upon which is a small waterfall. The Glen and Till unite at Ewart, and from this point, or further down, when the evening sun is sinking behind, is, we think, the finest view of the Cheviots. The mass rises up clearly defined from the level country, the rounded tors in front, and behind them the higher hills over Langlee-ford and Southernknow, and highest of all, the great ridge of Cheviot itself, and the slightly lower rounded summit of Hedgehope. Past castles and villages famous in history and border story, the Till flows with many windings northward. The last low swell, crested with fir trees, where the hill-country sinks into the plain, is Flodden Edge, and that rich corn-land at its base is Branxton Lea. The castles and parks of Twizell, Etal, and Ford pleasantly diversify the last 5 miles of the stream, which joins the Tweed 10 miles below Ewart.
This district measures about 20 miles long by from 10 to 15 miles broad, and is about 250 square miles in area, of which the Cheviot mass occupies more than one-third.
ALTITUDES.
(Those marked with a star are communicated by Sir Henry James, Director-General of the Ordnance Survey, the others generally measured from these as a basis by the Aneroid barometer. )
| FEET. | FEET. | |||||||
|
* |
| ||||||
|
* |
|
* | |||||
|
| |||||||
|
* |
| ||||||
|
|
|||||||
|
|
* | ||||||
|
|
* | ||||||
|
||||||||
|
|
* |
2. NORTH-EASTERN DISTRICT.
This is a long narrow tract extending 30 miles along the coast, from the Tweed nearly to the Aln, through which flow several small streams from west to east. From the plain of the Till on the west, it is separated by the range of sandstone and basaltic moor, which has been mentioned already. Ross Castle, the highest point of the range (see above), is at the point where districts one, two, and three meet. For some distance northward the ridge is often 3 or 4 miles broad, with a decided slope on both sides, and is but little planted or cultivated. For 8 miles it maintains this character of heathery moor, the most interesting plants being Myrica gale, Listera cordata and Trientalis europaea, all of which occur in considerable plenty. Black Heddon, north of Belford, is a conspicuous heathery ridge, between 600 and 700 feet in altitude, with a base of arenaceous crag. On the north-east, parallel with Black Heddon, but extending beyond it in a northern direction, are Kyloe Crags, the finest range of basaltic cliffs in the northern part of the county. This ridge is a mile in length and slopes towards the sea, which is not more than 2 miles distant. The direction is from north-west to south-east, and the highest point a little under 600 feet. The seaward slope is gradual and grassy, but the opposite face is precipitous, the actual cliff being not more than 20 feet or 30 feet in depth; but the bank beneath it, about 50 feet in all, is steep and thickly covered with basaltic debris. A list of the plants of this crag has been already given. The sandstone sweeps down from Black Heddon to underlie the basalt, and on the north never recovers its altitude. For several miles northward the ridge is only about 400 feet in altitude, and beyond Lowick it is even lower, but still, in many places, only partially cultivated. From Berwick southward to Belford the coast is low and sandy. There are three principal streams, but the low cultivated country between the ridge and the sea is only from 2 to 4 miles broad. The northern part of Holy Island is a sweep of low waste sand-hill, but on the south, about the castle and the village, the basalt appears. Along the low stretch of sandy shore opposite Holy Island, from Ross Point past Fenham to Beal, is one of the best stations along the coast for maritime plants. Above Easington and Belford small patches of basaltic crag again appear. Next comes a longer stream called the Warn Burn, which flows down a wooded hollow past Twizell House to the sea. On the east of this the basaltic crags stretch with interruptions from Spindlestone to the coast at Bambro'. This part of the ridge yields several interesting plants, amongst which are Spiraea filipendula, Hieracium pallidum, Vicia lathyroides, Allium schoenoprasum, Moenchia erecta, Potentilla alpestris, Sedum villosum, and Arenaria verna. The last three are plants of such well-marked montane character that their occurrence here is worthy of attention, as the ridge is under 150 yards in altitude, and quite isolated from any of the higher hills, and the Arenaria does not occur anywhere else in Cheviot-land. The basalt comes out in full force along the shore from Bambro' southward. The Farne Islands are all basaltic outliers, and past Beadnell, Swinhoe, and Embleton to Cullernose, near the Howick grounds, are several fine faces of crag, with low sandy depressions between them. The area of this district is about 150 square miles.
ALTITUDES.
| FEET. | FEET. | |||||
|
* |
| ||||
|
| |||||
|
3. ALN DISTRICT.[9]
The main branch of the Aln has its sources on the eastern slope of the Cheviot range near to Alnham, where the junction of a few sikes, or mountain streamlets, forms the Ale-water. The highest hills at the head of the vale of the Aln are the Grey Yade of Coppall (900 feet), and Cochrane Pike (1096 feet), which, like the other Cheviot hills, are bare and grassy, with here and there an outbreak of porphyritic rock. The general course of the river is from west to east, and its length about 24 miles. The upper portion flows in a pretty wide valley, between the porphyritic hills on the north and the great sandstone ridge on the south and south-east. It skirts the base of this ridge for 11 miles till it reaches Brislaw, where it cuts through the ridge which, at the Beacon Hill on Alnwick Moor, attains 808 feet; and after crossing Hulme Park, which extends about 3 miles, and, passing by Hulme and Alnwick Abbeys and Alnwick Castle, it winds its way south-eastward and falls into the sea at Alnmouth.
The drainage area of the upper portion is from 3 to 11 miles wide, the principal affluents on the south being the Coo and Edlingham Burns, which are more than 5 miles in length, and drain the moorlands of the sandstone ridge about Coo Crag (1004 feet), and of Rimside (816 feet), where there is a station for Cornus suecica. The ridge is here several miles broad, heathery, and in many places boggy, and extends southward without interruption to the Coquet. On its eastern slope Rugley Burn has its source in Alnwick Moor and in Rugley Old Dene; by the side of this burn grow Carduus heterophyllus, Crepis succisaefolia, and Gagea lutea. On the north of the Aln two branch-streams, Eglingham and Shipley Burns, which have a course of about 6 miles, and unite and join the Aln near Shipley, have their sources in the Chillingham and Charlton Moors, which have an elevation of from 600 to 1000 feet. At the base of the Eglingham hills is Kimmer Lough, now about 9 acres in extent, but formerly much larger.The lower part of the vale of the Aln is not more than from 2 to 4 miles wide. The most interesting botanical station near Alnwick is Ratcheugh Crag, another portion of the basaltic dike which from this point runs across the county in a south-western direction. Here occur Sesleria caerulea, Astragalus glycyphyllos and Astragalus hypoglottis, Geranium sanguineum, Dianthus deltoides, Moenchia erecta, and several other interesting species. The area of this district is about 150 square miles. None of the hills, except those west of Alnham, rise distinctly into the Middle zone.
ALTITUDES.
| FEET. | FEET. | ||||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
| ||||||
|
|
4. COQUET DISTRICT.
The course of the Coquet is nearly in a line from west to east, and its length about 40 miles. For several miles its watershed ridge on the north forms the boundary between England and Scotland. The upper part of the dale has entirely the characteristic Cheviot aspect—a narrow grassy hollow, with a stony unenclosed moorland road, at the bottom a brawling mountain streamlet, excellent for trout-fishing, grassy hills rising steeply from this on either bank, very little actual crag, and what there is usually down by the stream-side, but often great sweeps of porphyritic debris stretching down the banks, flecked with green of brake and purple of foxglove. At the corner, between the Usway Burn and the Breamish, Windygyle is quite 2000 feet in altitude, and between the Alwine and Hedgehope, Cushat Law and Weather Cairn reach 2019 and 1836 feet. From this point the ridge westward along the Scotch border, though further up the river is not so high. Between the two forks of the Coquet, where Watling Street crosses the border, Chew Green Camps are 1436 feet in altitude. From this point down to Alwinton the distance is 14 miles. The most interesting point of the river is at Linn Shiels, 2 miles west of Alwinton. Here, on the east, a precipice of porphyritic crag rises from the stream to a height of 100 feet above it. The opposite bank is also steep and craggy, and a horse-shoe shaped ravine is formed, at the bottom of which the stream, pent within a narrow channel of rock, flows in a succession of leaps and dark peaty pools. This is the point at which, proceeding downwards, the sedimentary strata are first reached in the bed of the river; and below the ravine the Tuedian flagstones may be seen clearly dipping towards the south-east at a steep angle of inclination. The Ridlees Burn, which joins the Coquet just below, is almost coincident along its whole course with the line where the porphyry ceases. At Windyhaugh, 6 miles from its source, the Coquet is only 830 feet above sea-level, and at Alwinton, 8 miles lower down, it has sunk to 500 feet. In the corner between the Alwine and the Coquet, the hills rise to a height of about 1000 feet. The upper part of the Alwine has the same character as that of the Coquet, so that this drainage tract contains almost as much porphyritic hill and dale country as the first district, a tract of about 70 square miles in area, stretching from Alwinton away to the north and west, steep ridges and high rounded knolls with bare grassy banks, diversified but rarely by those same sweeps of grey or brick-red porphyritic rock of which we have already spoken, a monotonous and very lonely region, that seems to be given up almost entirely to the sheep. We have given already a list of the plants of one of the Alwinton cliffs, and must now take a final leave of the porphyritic region. Between Alwinton and Rothbury, on the north side of the river, the ground, stretching away from the Coquet towards the head of the Aln, is flat and cultivated, hardly anywhere exceeding 500 feet above sea-level. The lowness of this tract, when the stream lower down on the same side is bordered by high heathery moorland, seems anomalous to one accustomed to the gradually rising banks of hill that usually margin the streams that flow from the Pennine chain on the east. On the south side of the Coquet the physical geography is more like what is usual. From Ridlees Cairn (1346 feet) to Simonside (1447 feet), a distance of 15 miles, stretches a bank of hill of an altogether different character from those we have left behind on the west, heathery and plateau-like, forming at first the watershed between the Coquet and the Reed, and afterwards between the Coquet and upper part of the Wansbeck. Harbottle Lough, a lonely little tarn in the heart of hill a mile south-west of the village of Harbottle, with flocks of screaming sea-gulls wheeling about it in summer-time, and swamps of Comarum, Menyanthes, Equisetum limosum, and cotton-grass, and sweeps of heathery moor fragrant with gale and juniper, stretching far away towards Redesdale on the south, and ridges of grey gritstone crag shutting it in on every side, is well worthy of a visit. The edge of moor at this point is barely 1000 feet above sea-level, and the gradual slopes about Harbottle and Holystone are covered with fir-plantations, and in one place a natural wood of oak and birch stretches down to the road-side. At Holystone, close to the village, is the well of Paulinus, a small spring of water, crystal-clear, one of the places where the indefatigable missionary baptised an indefinite number of converts, as a statue and inscription commemorate. All along this part the north side of the river has nothing of the mountain aspect; but above Rothbury, where the stream has sunk to under 100 yards above the sea-level, we strike the sandstone ridge in its northward course transversely, the hills again attaining a height of 1000 feet, and rising above the town with considerable steepness, crested with edges of gritstone crag. A streamlet which flows down from this hill is called Hebden Burn. Simonside is a characteristic feature of Northumbrian physical geography, a great mass of hill rising up in the very centre of the county to a height of 1500 feet, and commanding nearly the whole of it at a single view. From the loosely-piled cairn of stones that marks the highest point the eye stretches on the north to the Cheviot ridge, Cheviot and Hedgehope standing out like two camel-shaped humps prominently in front, to the west a slightly lower continuous ridge sweeping away to bound the view for a quarter of a circle, and on the east a spur prolonged from them in the direction of the head of the Aln. The foreground in front of this wall-like ridge consists of a broad space of comparatively low cultivated country, of which Alwinton, Alnham, and Rothbury are the limits, brown fallows, bright-green fields of grain, duller green pastures and meadows, very little wood, and what there is not in patches but principally scattered trees in the hedgerows and along the streams, the Coquet winding along the dale, sometimes hidden, sometimes gleaming in the sunshine. To the east rises the heathery moor which runs without a break from Rothbury northward to the Aln, scattered over with edges of grey gritstone rock. The western hill shuts out the view of the Harbottle fir-woods and upper part of the Coquet valley, but on the right the long line of coast from the Aln to the Tyne can be clearly seen; and due south a wide tract of low undulated moory country across the Wansbeck and Tyne to Kilhope Law and the Durham fells, and further west the similar valleys of the Reed and North Tyne, with the Lake hills far away over them on the distant horizon. Eastward of Rothbury the watershed ridge on both sides of the valley declines rapidly, and soon assumes the character of low cultivated country. On the south it is 600 feet in altitude above Long Horsley, and on the north 473 feet at Shillmoor. Past Brinkburn Priory, Felton village, Acklington Park, and the castle and priory of Warkworth, margined often, like its neighbour-streams the Aln and Wansbeck, with steep wooded banks, the Coquet flows with many windings to its mouth at Warkworth Harbour. The total area of the district is about 250 square miles.
ALTITUDES.
| FEET. | FEET. | ||||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
* |
| |||||
|
|||||||
|
| ||||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
* |
|
* | ||||
|
|
* |
5. WANSBECK DISTRICT.
The numerous east-flowing streams which join to form the Wansbeck come from a tract which, from Simonside towards the Tyne, stretches for 10 or 12 miles through the heart of the county, a tract of very thinly-inhabited low grassy moorish country, the ridges running west and east, not more than from 600 to 800 feet in elevation, with very little crag upon them, but often covered with plantations of Scotch fir, spruce, and larch, and the hollows in various stages of transition between pasture and grassy moor. The northern fork rises in Bodle Moss, on the southern slope of Simonside, and joins a streamlet from Darden Rig to form the Font. Amongst the swamps of the upper part of this branch the Andromeda grows; and Chartner's Lough, a little mountain tarn near the head of the northern fork, is the station for Nuphar intermedium. This drains the country between Long Horsley and Elsdon, and is the most wooded fork of the river, flowing from the moors south-eastward past Nunnykirk, Netherwitton, Pigdon Woods, and Newton Park, to join the main stream at Mitford. The next fork comes from the east slope of the Ottercaps and the moors round Catcherside and Harwood. It is a small fir plantation just north of the railway, near the head of one of the branches of this fork, that yields the Linnæa. Rothley Lake is a tarn amplified by artificial means at the head of another branch, and lower down are Rothley Castle and Hartburn Grange. The main branch begins 2 miles eastward of Reedsmouth and flows through Sweethope Lough, a moorland tarn said to cover 180 acres, with swamps round it of Typha, Carex ampullacea, and Sparganium ramosum, to Kirkwhelpington, south of which the basalt crops out prominently in Thockrington and Bavington Crags, the only places where it is conspicuous between Gunnerton and Alnwick. At Wallington the stream is a mere brook, some 6 or 8 yards across, between grassy pastures, with the fine old hall and its rich woods looking down upon it from an easy slope on the north. About Meldon and Mitford the banks are deep and pleasantly wooded. Below this latter village there is a steep bank planted with beech and sycamore for at least a mile on the north side of the stream, and the bed is in some places filled with rock and overhung with alder, bird-cherry, and willows, amongst which grow Trollius, Myrrhis, Crepis paludosa, and Cardamine amara. The town of Morpeth is situated in a hollow but little above the level of the stream 5 miles from its mouth, with wooded banks rising rather abruptly to a height of about 100 feet to enclose it.
It is a pleasant ride in summer-time from Morpeth by the coach to Long Horsley, up a gradual ascent through a thinly-populated and thinly-cultivated country where brake, furze, and broom still linger in the lanes, and honeysuckle and wild roses cluster in the hedges, till at last the brow of the bank is gained, and Simonside and the Cheviots leap up suddenly into view. The stream is large enough to admit small vessels as high as Morpeth, and flows between deep wooded banks below Bothal Castle into an estuary at Camboise. The area of the district is about 200 square miles.
| FEET. | |
| Simonside | 1447* |
| Cockhill | 367* |
| Rufflaw | 597 |
| Meldon Bridge | 243* |
| Morpeth Bridge | 94* |
| Point quarter of a mile north of Hebron Village | 376* |
6. NORTH TYNE DISTRICT.
This district has an area of about 400 square miles, embracing a tract 20 miles across in both directions, including the western border of the county from the Cheviots southward for half the distance to the Durham border, a large proportion of its surface being uncultivated grassy or heath-clad moor between 500 and 1000 feet in elevation. For 25 miles the watershed ridge of the two branches of the North Tyne forms the boundary between Northumberland and Roxburghshire. For 15 miles from north-west to south-east the two dales, Redesdale and North Tynedale, run parallel with one another, broad grassy dales with villages and farm-houses thinly scattered at the bottom or along the banks and winding streams with numerous branches that lead up gradually into the recesses of the moors. Between the Reed-water and upper part of the Coquet there is a broad continuous ridge of heathery grit-crested moor, of which the highest point, Ridlees Cairn, attains 1346 feet. Carter Fell, on the south of the road on the Scotch border, at the very head of the Reed overlooking Liddesdale, attains 1600 feet. Near the head of the Chattlehope Burn, the first stream of any consequence that falls into the Reedwater in the west is a fine waterfall amongst the moors called Chattlehope Spout. The upper part of this dale is very thinly populated, and seldom visited; but during the last two hundred years the hand of agricultural improvement has been steadily at work, and the wide morasses and neglected heaths of the days of the moss-troopers have been many of them drained and turned into sheep-walks, and here, as further north, of the natural forests of the glens, the primeval woods of birch, alder, oak, rowan, and willow, but few relics remain. At Rochester, 10 miles south-east of Carter Fell, are marks of Roman occupation. A few miles lower down is Otterburn, the scene of the skirmish between the Percies and Douglasses, which the ballad of Chevy Chase commemorates, and then comes Elsdon, the principal village of the dale. Here Redesdale may be considered to end. On each side a conspicuous hill, under 1000 feet in height, rises up to guard the entrance, that on the west called Hareshaw Moor, and that on the east the Ottercaps; and the stream turns suddenly to the south-west, flowing 6 miles in that direction before it joins the North Tyne at Reedsmouth.
The North Tyne rises in a broad hollow on the western edge of the county, being formed by the union of several streams which flow from a crescent of heathery gritstone hills extending from Carter Fell, Carlingtooth Fell, Peel Fell, and Deadwater Fell, southward to the head of the Cairncleugh Burn, the first-mentioned peak 1600 feet, but the others only from 1000 feet to 1300 feet in altitude. In the 15 miles which it flows eastward before the Reedwater joins it, the ridge on the north has sunk to 800 feet. This is penetrated by one principal stream, the two branches of which are called the Tarret and Tarset. The Border Counties Railway now runs along the whole length of the dale and passes out at its head, forming one of the principal lines of communication between Newcastle and Edinburgh. Above Bellingham the population is thin, and the villages are very small. There are considerable plantations about Kielder Castle and Hesleyside, and workable collieries at Kielder and Falstone. In the neighbourhood of Smalesmouth is the station for Convallaria verticillata. On the south, between the North Tyne and Irthing, is a wide space of barren moor, crested in some places with edges of gritstone, which rises scarcely anywhere above 1000 feet, and on this side the ascent from the river is very gradual. At Bellingham the stream is from 30 to 40 yards across, and 375 feet above sea-level. Here it is joined by the Hareshaw Burn on the north, on which is Hareshaw Linn, the finest of the Northumbrian waterfalls. The waterfall is about a mile distant from the town. Just above the railway we have to climb over the shale heaps of the iron-works. Then the sides of the glen become steeper and we lose sight of the town and surrounding moors, and enter a winding ravine where uncertain wandering paths lead up and down amongst the trees and underwood. First the lower fall is reached, a perpendicular ledge of rock some 20 feet in height, over which the stream breaks in two places, the rocks continued on both sides a little distance down the glen. The principal fall is about half a mile further up, and is of a much more important character. On the left a precipice rises up without break to a height of nearly 100 feet, one sheer wall of massive rock, brown and cool towards the base, with green mosses in the crevices; higher up, where the sun sometimes catches it, bare brown and white, or yellow- stained with lichen, the summit clothed with ivy and bird-cherry, and waving branches of elm and rowan. The stream flows from an opening half-way down between this cliff and its counterpart on the opposite side, forming, not a large waterfall, but one where nature has made the most of the volume of water she has had to work with, for the the cliff, contrary to the ordinary plan in the North of England cascades of small side-streams, projects at the base considerably more than at the ledge, so that the water falls down an irregular slope of hard gritstone rock, the jagged projections of which break it into foam and spray, and innumerable sparkling eddies. The tall slightly-overhanging side-cliffs of the glen converge crescent-wise towards the fall and shut in a cool ravine where such plants as woodruff, golden saxifrage, Cardamine sylvatica, and Campanula latifolia luxuriate, and where we may gather oak fern, beech fern, and Trollius, Rubus saxatilis, Epilolium angustifolium, and Crepis succisaefolia.
After the junction of the Reed water and North Tyne the stream and dale run south and rather south-east for 14 miles. The ridges on each side are not more than 400 feet above the river, and for the northern half of the 14 miles especially there is but little of the dale character. The bank of the stream is often steep and pleasantly-wooded, and there are several villages of considerable size (Wark, Barrasford, Chollerton, Wall, Humshaugh), and halls and castles at Haughton, Chipchase, Simonburn, and Nun wick by the side of the river, or hidden amongst the trees. The most considerable woods of this lower part of North Tynedale are those of Countess Park, near Reedsmouth, and of Chipchase, Nunwick, Chesters, and Warden Hill. On the east side of the dale, above Barrasford, the basalt stands out prominently at the top of the bank, with a precipitous escarpment facing the north (Gunnerton Crags), south of which the bank of the dale is steeper and the ridge more hill-like. On the west Wark Burn rises on the edge of the county and flows for 10 miles eastward through the moors before it joins the main stream. The basalt shows itself upon its banks at Rose's Bower and forms a small waterfall, but the principal basaltic cliff on the west side of the river is further south, and does not belong to this drainage tract. One of the forks of the branch that joins the Tyne at Nunwick, comes from the lakes on the north side of the Roman wall. These are situated in the very heart of the heathery treeless moor, at an elevation above sea-level of from 200 to 250 yards. Greenley Lough is about three-quarters of a mile longby a quarter broad, Little Cow Lough half a mile long, and Broomley Lough broader and shorter. At Tecket, at the head of a fine wooded dene which extends down to Simonburn, this same stream forms a waterfall, spreading out first for 30 or 40 yards over a channel of hard rock, overhung by ash and elm, with woodruff, sanicle, and oak-fern, and cool bright mosses, such as Milium hornum, Dicranum pellucidum, and Hypnum rivulare in the crevices, and then leaping over a crag some 20 or 30 feet in height amongst tumbled boulders. In the dene below the fall grow Rubus saxatilis, Agrimonia odorata, Carduus heterophyllus, Vicia sylvatica, Crepis succisaefolia, and Hieracium prenanthoides, and soon the stream totally disappears from its rocky channel only to reappear more than a mile lower down. In the lower part of the dale we trace the influence of the drier rocks in the appearance or increased abundance of such plants as Knautia, Scabiosa columbaria, Betony, Thymus, Galium mollugo, Silene inflata, Poterium sanguisorba, Agrimony, Campanula glomerata, Origanum vulgare, Arabis hirsuta, and Geranium lucidum. Warden Hill, crested with firwoods, rises to a height of 450 feet above Chollerford, standing out boldly into the angle between the North and South Tyne, and commanding an extensive view in every direction.
ALTITUDES.
| FEET. | FEET. | |||||||
|
|
* | ||||||
|
* |
|
* | |||||
|
|
|||||||
|
* |
|
||||||
|
* |
| ||||||
|
* |
|
||||||
|
* |
|
* | |||||
|
|
7. SOUTH TYNE AND ALLEN DISTRICT.
This district occupies the south-western corner of the county, and contains a greater extent of moor that rises into the Middle zone than any of the others except the first. For 12 miles on the west the Irthing forms the county boundary, with small branches that penetrate the moors on the Northumbrian side. The gritstone edge (Muckle Samuel's Crags) of the watershed between its head and the North Tyne is 1108 feet in elevation, and Whitehill, rather lower down, is 943 feet. Above Wardrew it is a mere moorland stream, but there is a waterfall called Cromel Linn, and lower down to Gilsland the banks are wooded, yielding Saxifraga aizoides, Equisetum variegatum, Galium boreale, and other plants scarcely to be expected at an altitude of between 300 and 400 feet. The pass over which the railway crosses, between the South Tyne and Irthing valleys, is little over 400 feet in elevation, and is the lowest point of the Pennine watershed, which divides the streams of the west from those of the east coast between the Cheviots and the Trent. A moorish swamp called Baron House Bog borders the railway here, and yields Lysimachia vulgaris, Ranunculus lingua, Carex limosa and filiformis, and abundance of Vaccinium uliginosum. Here the Irthing leaves the county to fall into the Eden above Carlisle. The main branch of the South Tyne rises in Cumberland not far from the head of the Tees. At Alston it is 900 feet in elevation, and in the 12 miles that it flows due north it declines on the average 45 feet per mile. Between Knaresdale and Allendale is a ridge of high moor, which reaches 1645 feet on Whitfield Common, and 975 feet over Plainmeller, 2 miles south of the railway. Below the castle and park of Featherstone the Tipple Burn, a considerable stream from the moors on the north, breaks through the basaltic ridge and flowing past the ruined castles of Blenkinsop and Thirl wall, joins the main stream, which turns suddenly due east and flows in that direction 50 miles before it falls into the sea. Between Haltwhistle and Hexham we have what is usually called South Tynedale, a hollow 15 miles in length, with the hills rising from it gradually on both sides. On the north the most striking feature is the basaltic dike, which in some places reaches a height of 700 or 800 feet above sea-level, forming a decided ridge across the moor from west to east, with an escarpment towards the north which, in several places, consists of a cliff 20 or 30 feet in depth, as at Kyloe, with great heaps of angular slate-coloured basaltic debris scattered over the embankment below it. For several miles along the top of this ridge, with nothing on either side but heathery moor, the Roman wall is carried, following the irregularities of the ridge with pertinacious adherence. Rising from the Black Burn west of Featherstone Castle, where the water, after running for some distance in a deep and narrow channel is thrown over a columnar cliff in a succession of falls, from which the broken sedimentary rocks dip at every angle, and from the wild ravines called the Nine Nicks of Thirwell, between the Tipple and Haltwhistle Burns, the ridge forms Wall Town Crags and Cockmount, and thence sweeps with a slight tendency towards the north by way of Sewing Shields, Black Bank, and Crag Lough, in the direction of Wall and Gunnerton. Crag Lough is a tarn half a mile in length, with a fine cliff of the kind just alluded to rising up from the water's edge on the south side. Muckle Moss is a large swamp upon the hill slope 2 miles to the south-east, which is well-known as a botanical station. By means of the Newcastle and Carlisle Railway this tract is all brought within the compass of a day's excursion from Newcastle. Round the head of the two branches of the Allen for 10 miles a continuous ridge of high heathery fell forms the watershed between Tyne, Wear, and Derwent. The highest points are near the centre—Kilhope Law, 2206 feet, and Stangend Rigg, 2074 feet; but for the whole 10 miles the ridge scarcely sinks below 1700 feet, and the spurs in a northern direction maintain a sufficient height for several miles to give East and West Allendale more of a decided dale character than any other of the Northumbrian valleys. This is well known as a rich mining tract. The limestone is thrown down to the level of the river in the western, and below the level in the eastern hollow in the upper part, so that the higher reaches of the main streams have very little to diversify them, and the hills are undulated sweeps of the ordinary kind of heathery gritstone fell. We have given already a list of the plants noted in the Upper zone on Kilhope Law. As tested either by number of species or individuals the boreal element of the Flora is considerably smaller than in Weardale, and still more so than in Teesdale. The principal interest of the district, from a botanical point of view, arises from the extent and perseverance with which agricultural and horticultural cultivation has been carried on at, for Britain, an unprecedentedly high altitude; but as full details have been given in the chapter on climate, both as to species and the heights to which they are grown, we need not say more about the subject here. At the head of West Allendale there is a village of perhaps thirty houses, called Coal Cleugh, at a height of from 1600 to 1700 feet[10] above sea-level. Above Allenheads the slopes are everywhere clothed with extensive plantations of Scotch fir and other Coniferee, and at the bottom of the hollow stands Mr. Beaumont's hall in the midst of its well-ordered grounds, and in front down the river extends a village half a mile in length, with a church and school-house, and a large number of cottages and gardens, and in the centre the mining office and entrance to the great shaft, a model mining village for order and cleanliness, at a height above sea-level of from 1350 to 1450 feet. The town of Allenton is 9 miles below Allenheads, near the point where the East and West Allen unite. From Whitfield all the way down to the Tyne the banks of the Allen are bordered with woods, and in some places, as for instance about the old castle or Peel of Staward, which stands out towards the river on a rounded rocky promontory, with a steep wooded bank on the opposite side and a high heathery moor in the back ground, they rise for 100 feet above it with much abruptness. At Gatton the watershed between the Allen and the stream on the east has sunk to 1000 feet, but there is still a well-marked ridge in the direction of Hexham with a gradual slope of cultivated country towards Langlee Castle and Haydon Bridge, about 250 square miles. The area of the district is about 250 square miles.
ALTITUDES.
| FEET. | FEET. | |||||||
|
* |
|
||||||
|
* |
|
* | |||||
|
* |
|
* | |||||
|
* |
|
* | |||||
|
* |
|
* | |||||
|
* |
|
* | |||||
|
* |
|
||||||
|
* |
|
||||||
|
* |
| ||||||
|
||||||||
|
* | |||||||
|
* |
8. SOUTH-EAST DISTRICT.
This district includes an area of about 300 square miles, a large proportion of which belongs to the Coal country, and only a small portion at the south-western corner rises above the Lower zone. From the point where the North and South Tyne join and Hexham stands like an old Rhine city on a hill that rises from the south bank of the river, over-topped by the massive grey towers of its church and castle, the distance to the mouth of the river is 30 miles. At Hexham there is a bridge of twelve arches, and the stream is 100 feet above sea-level. The first stream on the south is called the Devil's Water and joins the Tyne at Corbridge. It has two long branches on the west called the Rowley Water and Dipton Burn, and the ridge in the direction of Allendale is distinctly marked, attaining 1200 feet towards the head of the stream and maintaining a height of 600 or 500 feet within a short distance of Hexham. From the last 6 miles, from the foot of Dukesfield Common past Woolley and Dilston, the main branch has its banks wooded almost continuously, and parallel with the Tyne, at a height of above 400 feet, a long sweep of fir plantation stretches from Dilston eastward, and further back, between Slealey and the Derwent, is a bank of heathery moor within 5 miles of the Tyne, which extends eastward as far as Shotley and Minster-acres House, with an elevation of from 900 to 1000 feet. The Derwent forms the boundary of the district for 15 miles on the south, but its upper branches on the Northumbrian side are very inconsiderable. At Allansford Bridge it is 400 feet in altitude, and at Shotley Bridge 50 feet lower. Two pleasant wooded denes stretch down from the moor to the Tyne at Biding Mills and Bywell. North of the Tyne there is a gradually-sloping bank, cultivated and in some places wooded, which attains 490 feet above Corbridge, 520 feet at Heddon, and 400 feet opposite Newcastle. The principal wooded denes of the north side of the river are Whittle Dene near Ovingham, Walbottle Dene near Newburn, Scotswood Dene above Scotswood, and Heaton Dene below Newcastle, none of them more than about 2 miles in length, and the latter especially, like the last 15 miles of the Tyne, with but little of the indigenous vegetation still lingering. The collieries are principally concentrated in the area between Newburn, Blyth, and Shields. There are two small streams between the Tyne and Wansbeck, which are called the Pont and Blyth, the former of which is connected with Prestwick Carr, a large morass in the low country 4 miles north of Newcastle, which was once a good botanical locality, but is now enclosed and almost destroyed by drainage. Except about Whitley and Tynemouth this part of the coast is low and sandy, but in some of the wooded denes of the interior several of the Montane plants are scattered.
ALTITUDES.
| FEET. | FEET. | |||||||
|
| |||||||
|
|
* | ||||||
|
* |
|
* | |||||
|
* |
|
* | |||||
|
|
* | ||||||
|
||||||||
|
9. DERWENT DISTRICT.
The Derwent takes its rise by two branches, both of which begin a short distance east of Allenheads. The northern one is called the Beldon Burn, the southern one the Knucton Burn. After a course of 5 miles each they join at Hunstanworth, and the river takes the name of Derwent, and, flowing in a north-eastern direction, forms for nearly 20 miles the boundary between the counties. The hills of the upper part consist of undulated heathery fells of the ordinary gritstone character. Redburn Edge, in a line with Stangend Rigg, at the head of the Knucton Burn, is 1833 feet in elevation, and a ridge of high moor extends from this several miles due east to Bolt's Law (1772 feet), and Stanhope Common (1712 feet). Between the two burns the ridge is called Knucton Fell, and attains 1561 feet. A small stream from Bolt's Law, called Bolt's Bum, joins the main one at Bay Bridge, below Hunstanworth: the Burnhope Burn, a larger one from the same direction, drains the hollow between Edmundbyres and Muggleswick; and a third, the Hysehope Burn, takes its rise in the fells 3 miles south of the former village, and, after being joined by the Horsley Hope Burn, falls into the Derwent a little lower down. In different parts of the higher moorlands are to be seen, in situ, the remains of ancient birch-forests, the stumps of the fallen trees appearing above the peat; whilst the trunks of peat-buried oaks, of considerable size, give evidence of an ancient sylvan vegetation much superior to any in existence now. The Fell Top limestone first shows itself in the bed of a tributary of the Burnhope Burn, and below Muggleswick the Great Limestone appears in the bed of the Derwent, which winds very much in this part of its course through a picturesque wooded country. Then the stream turns north and leaves the great mass of moorland behind. At Cold Rowley the watershed ridge has declined in level to 900 feet, the stream at Allansford Bridge being just 500 feet below the top of the moor. Still, for several miles further, the steeply-sloping bank, on the east side of the stream, studded over with coal-mines and iron-works, keeps up a height of from 800 to 700 feet. At Shotley Bridge, where the line between the Millstone Grit and Coal Measures strikes the stream, the elevation is 350 feet. Very soon the county boundary leaves the Derwent and runs northward along the Stanley Burn to the Tyne at Wylam. On the north side of the Derwent the moor between Hedley and Chopwell Park attains 850 feet, and between Ryton and Winlaton a small stream runs down a wooded dene to the Tyne at Blaydon. Along the 10 miles due east, from Shotley by way of Medomsley and Tanfield to Ravensworth, the highest points of the undulated coal-country reach from 750 to 600 feet. The parks and halls of Chopwell, Gibside, and Axwell pleasantly diversify the last 5 miles of the Derwent, which joins the Tyne a short distance above Newcastle. The undulated coal-country south of Newcastle is drained by a small stream called the Team, with a wooded dene at Tanfield, and a castle and park upon its banks at Ravensworth. A narrow tract of Magnesian Limestone belongs to this drainage district, the highest point of which is at West Boldon (307 feet), whence a rivulet runs down to the Tyne at Jarrow. The area of the district is about 200 square miles.
| FEET. | FEET. | ||||
|
| ||||
| |||||
|
| ||||
|
| ||||
| |||||
| |||||
|
10. WEAR DISTRICT.
The county of Durham, towards its western extremity, does not measure more than 10 miles across. The Derwent does not attain the county boundary, and this 10 miles includes the whole breadth of the tract drained by the Wear and half of that drained by the Tees, the other half belonging to Yorkshire. The Wear watershed forms the eastern boundary of Cumberland for 6 miles, and for the same distance on the north separates Durham and Northumberland. Round the head of the dale sweeps a continuous crescent of high barren grassy or heathery fell, several of the peaks of which exceed 700 yards, whilst the passes into Cumberland, Teesdale, and Allendale are all from 500 to 600 yards in elevation. Due south of Allenheads, only a very short distance from the highest point of the road from Allendale to Wear Head village, Stangend Rigg attains 2075 feet. At the extreme north-west of the county Kilhope Law reaches 2206 feet, with a view extending northward over Whitfield Fell to Simonside and the Cheviots. The four peaks of the western watershed ridge, proceeding from north to south, are Knoutberry Hill (2195 feet), (the knoutberry is Rubus chamaemorus, which grows on the upper part of all these fells in profusion), Dead Stones (2326 feet), Burnhope Seat (2368 feet, the highest point in the county), and Ashgill Head (2274 feet). From the village of St. John's Chapel five glens radiate towards the south-west, west, and north-west, like spokes from the axis of a wheel, Kilhope, Welhope, Burnhope, Irishope, and Harthope. On the west side of the boundary peaks just mentioned, we have the Main Limestone at an elevation of 700 yards. In Kilhope, Welhope, and Burnhope it forms crags along the edge of the fells at from 550 to 600 yards, so that everywhere in the peaks masses of gritstone overlie it. Proceeding eastward, before reaching any of the villages, Burtreeford Dike is encountered, which throws down the beds towards the east not less than 90 fathoms. This crosses the upper part of Irishope, bending due north across the lower part of Burnhope and the united burns of Kilhope and Welhope, turns a little eastward, so as to margin with limestone crags the highest point of the Weardale and Allendale road, and then crosses the county boundary. None of these western hopes show much of the limestone cliff. In Burnhope there is a curious bank of crumbling dark-coloured shale with a natural wood of birch, alder, and stunted willows, in which grow Crepis succisaefolia, Carduus heterophyllus, and Hieracium gothicum and tridentatum. At Wearhead (1100 feet), the highest village in the dale, the stream has already attained a considerable size. Black Dene on the north is a steeply sloping short, wooded hollow shaped like the letter Y. There are not here, as in Allendale, many fir plantations at a considerable height on the moor, little crag is to be seen, but the stream is broad, and its channel pleasantly diversified by shelves and boulders of massive blue limestone rock. The population of the dale is considerable; neat, wide-spreading villages, with churches, chapels, and school-houses succeeding each other rapidly at the bottom of the valley, while farm-houses dot the green fields that extend up the hill-side. The ridge in this part is 1000 feet above the stream and the bank is tolerably steep, the distance between the watershed line on the north and south being generally about 6 miles. The upper part of Weardale resembles Wensleydale or Swaledale far more than it does Teesdale, Allendale, or North or South Tynedale. Teesdale is much wilder in its scenery, and altogether exceptional in its botany, and none of the Northumbrian dales have the limestone in their upper part. The village of St. John's Chapel, 2 miles east from Wear Head, is perhaps the most convenient centre for exploring the upper part of the dale; the neighbouring ravine of Harthope, where a little stream tumbles over a succession of limestone edges, is the most picturesque bit of scenery in the neighbourhood. From St. John's Chapel eastward to Stanhope, a distance of 6 miles, the villages are fewer. On the south the glens of Swinhope, Westenhope, and Snowhope, each about 3 miles in length, open out into the main dale, and on the north the more considerable dale of Rookhope, 8 miles in length from the north-west, beginning within a very short distance of Allenheads. In Rookhope are the valuable mines of the Weardale Iron Company, and the limestone shows itself at 1100 feet.
The bridge over Stanhope Burn, at the west end of the town, is 670 feet above sea-level, and the limestone crops out on the hill-side at 800 to 850 feet. The moor upon the north of the town is still 1000 feet above it, the highest point being 1712 feet above sea-level, whilst on the south Monk's Moor, in the direction of Middleton, attains 1854 feet. Frosterley, which is situated 2 miles lower down, is about 500 feet high, and the limestone 150 yards. Above it Bollihope, a glen from the south-west opens out into the main dale, flanked in the lower part of it by a fine limestone cliff called Bishopley Crag. Soon the limestone dips below the surface, and as we proceed eastward is no more seen. At Wolsingham the Wear receives a small feeder from the north, which is familiar to the readers of Winch's Flora under the name of Westcrow Burn; soon afterwards the Bedburn also, which has several branches and drains a considerable tract of undulated gritstone moor that lies between Wolsingham and Eglestone, joins it upon the south. Now the bounding moors rapidly decline in level and we reach the line of the out-crop of the Coal Measures, which from Satley passes almost due south across the Wear tract by way of Towlaw, Harperley Gate, Witton-le-Wear, stretching, however, several miles to the west to curve round the head of the Auckland Valley, in which are situated several valuable mines. This Auckland stream rises amongst the high moors very near the Tees, in the vicinity of Eglestone, and, after a course of 20 miles towards the east, joins the main river at Bishop Auckland. From Wolsingham to this point, a distance of 12 miles, the course of the Wear has been towards the south-east. Here it turns at a right angle, and with many windings flows towards the north-east till it falls into the sea. How the rounded moors sink to 900 feet, then to 800 feet, and as we near Durham, to 600 feet. On the north the Browney, from Butsfield and Lanchester, drains a wide extent of moorish coal country, and upon the bank of the valley below it stand the park and castle of Brancepeth. The city of Durham, over-topped by the towers of its noble minster, occupies a commanding position on a hill, three sides of which are washed by the Wear, on the edge of the moorland. Between this and the western escarpment of the Magnesian Limestone lies the lowest ground in this part of the country, across which the main line of railway runs north and south. Past the ruins of Finchale Abbey, the villages of Cocken and Chester-le-Street, and the park and castle of Lambton, the Wear winds through this low country with often wooded and deeply excavated banks: the last 4 miles of its course it flows due east through a break in the limestone till it falls into the sea at Sunderland. The Magnesian Limestone attains the height of 488 feet at its highest point west of Newbottle.
This drainage tract includes the heart of the county from east to west, and comprises fully one half its total area.
| FEET. | FEET. | ||||
|
| ||||
|
| ||||
|
| ||||
|
| ||||
|
11. TEES DISTRICT.
The Tees rises in Cumberland, on the east side of Cross Fell (2901 feet). It first touches Durham at Crook Burn, 5 miles above the Caldron Snout, and for the whole of the remainder of its course forms the southern boundary of the county. This point is 1600 feet above sea-level, surrounded on all sides by desolate dreary moors. There is scarcely a lonelier tract anywhere in England than the expanse of wild moor that fills up the whole area between Alston, Langdon Bridge, and Dufton, 15 miles across in each direction, with hardly a house or a trace of cultivation to be seen. For 5 miles the river falls but little, but spreads out in a large tarn-like expansion called the Weel, quiet enough for Ranunculus peltatus and Potamogeton rufescens to grow in it. At the Caldron Snout the scene changes. First, the water becomes ruffled by shelves of rock, and then with a rush, the noise of which mingles with the whirr of grouse, and the bleating of mountain sheep far away amongst these lonely hills, the stream breaks a gorge through the great sweep of basalt, forming in doing so a series of broken rapids, leap after leap in tumultuous succession, the brown stream dashed by the first into an angry white foaming torrent rushing from ledge to ledge down a winding rocky channel, till at last it frees itself from the gorge and spreads out, like a ray of light as it issues from a prism, over a back-ground of broken sharp-edged basaltic columns. The total depth of the actual fall is 100 feet, and nowhere in Britain have we so deep a fall upon so large a stream. The best point of view for it as a whole is the open ground a short distance below on the Westmorland side of the river, from which the wooden bridge which spans the stream about half-way down the rapids (firm enough in reality) looks frail and dangerous. There is probably no piece of ground in Britain that produces so many rare plants within a limited space as Widdy Bank Fell. The distance from the Caldron Snout in a direct line due east to Langdon Bridge is 2 miles. The upper part of the fell is like an ordinary heathery moor, and the summit is only 130 feet above the head of the waterfall, which is 1530 feet above sea-level. Along the face of the hill towards the river sweeps a range of basaltic crags like those that form the waterfall, which are known by the name of Falcon Clints, broken, jagged, and irregular, with a bank of fallen blocks below the precipitous cliff for some 2 miles along the stream-side. Along the back of the hill from half a mile above the Caldron Snout eastward till they are thrown down by a fault into the east end of Falcon Clints, stretch low banks of Tyne-bottom limestone, bleached and rendered coarsely granular in texture by the proximity of the igneous rock, and from this copious streams flow down in three directions, westward towards the Weel, due eastward to Harwood Beck (this stream is called the Whey Sike), and south-east towards Widdy Bank House. Within an area of something like 4 square miles we have, upon the crags and banks of these streams, the following rare plants:
| Viola arenaria. | Hieracium pallidum, | |
| Arenaria uliginosa. | anglicum. | |
| Thalictrum alpinum. | Gentiana verna. | |
| Draba incana. | Arbutus uva-ursi. | |
| Potentilla alpestris. | Bartsia alpina. | |
| Sedum purpureum. | Elyna caricina. | |
| villosum. | Juncus triglumis. | |
| Saxifraga aizoides. | Carex capillaris. | |
| stellaris. | Sesleria caerulea. | |
| hypnoides. | Allosorus crispus. | |
| Galium boreale. | Asplenium viride. | |
| Hieracium iricum. | Woodsia ilvensis. |
| Polypodium calcareum. | Tofieldia palustris. | |
| Equisetum variegatum. | Scirpus pauciflorus. | |
| Poa Parnellii. | Armeria maritima. | |
| Galium sylvestre. | Primula farinosa. |
On the north of Widdy Bank the Main Limestone reaches an elevation of 1800 feet in Bleak Law, which extends from the Weel to the church in Harwood Dale, and above it the gritstone rises to 2028 feet. This first dale, Harwood Dale, is broad and open, the lower part being filled with grassy fields. There is a good road along the east side of it leading to Alston, and at its head Burnhope Seat attains 2368 feet, and Highfield, just above the Grasshill lead-mines, 2322 feet. The dale is 5 miles long from north to south, and joins Langdon Dale, a narrower dale with steep banks and very little population, at Langdon Bridge (1250 feet), and the united streams fall into the Tees a mile above the High Force. The flat stretch of ground round the point where the streams join is called the Whetstone Sill, and here begin Potentilla fruticosa, Salix phylicifolia, Habenaria albida, Crepis succisaefolia, Hieracium gothicum, crocatum, and corymbosum. East of Langdon Bridge the bank of the dale for several miles is steep and girdled conspicuously by the lines of limestone cliff, which, from 2100 feet in Highfield, decline very gradually towards Newbiggin Moor. The peaks of this ridge are Fendrith Hill (2284 feet) and Outberry Plain (2143 feet). From the foot of the Caldron Snout to the head of the High Force the Tees declines in level from 1430 to 1000 feet. The High Force is a very fine waterfall. Here the main stream of the Tees, its waters contracted often into a deep narrow channel, makes a sheer leap of 69 feet into a ravine, the cliffs of which margin the stream for a considerable distance below it. The cliff is dark-coloured basalt, resting upon a mass of dark-coloured indurated shale, and that upon limestone, and when the stream is full the waters flow upon both sides of the massive angular crag which overlooks the main descent. On the Durham side of the river the slope is covered by a large plantation, principally of spruce, and on the Yorkshire side the moor reaches down to the edge of the cliff. A more beautiful spot for a summer-day's excursion than this ravine, with its never-ending roar of waters, in front the cataract with its ceaseless rush and cloud of misty spray, at the bottom the dark foaming stream flowing rapidly amongst thickly-strewn boulders, margined in the open space below the cliffs with a grove of fantastically shaped juniper bushes, shut in above by its wood-covered slope and ledges of dark crag, can scarcely be desired. Between the High Force and Eglestone, a distance of 9 miles, four streams join the Tees on the north, the burns of Ettersgill, Bowlees, Hudshope, and Eglestone, but the hollows are scarcely more than mere moorland glens. There is a waterfall in the first called Hell Cleft, which is worthy of a visit. Between the High Force and where the Lune on the Yorkshire side joins the Tees the fall is 40 feet per mile. The river-channel is here considerably deeper than above the High Force, and especially during the first 2 miles, past Lower Cronkley Bridge and Winch Bridge there are rapids in the stream, and its banks are craggy and preprecipitous, and often margined with brush-wood and uncultivated moory ground. Above Newbiggin the ridge is 2200 feet in height, and the limestone full 500 yards. Above Eglestone extensive fir-plantations stretch from the town to the top of the moor. East of Newbiggin the limestone falls rapidly, and at Eglestone is lost from the bottom of the dale to reappear below Barnard Castle. The fells now decline to 1000 and 900 feet, but keep their height well up towards the river. North of Barnard Castle a stream rises on the edge of the moors at Langley Dale and flows through Baby to unite with another brook at Streatlam and join the Tees at Gainford. Below Barnard Castle, past Greta Bridge and Wycliffe, the Tees is again bordered by cliffs of limestone. None of the principal collieries fall within this drainage-tract. From Cockfield Fell, the ridge of hill which separates the Auckland from the Raby hollow, a dike of basalt runs south-eastward towards the Tees. At Pierce Bridge the Magnesian Limestone shows itself, trending north-eastward, with usually an escarpment towards the north-west, by way of Aycliffe and Ferryhill towards the Wear. The highest point which it reaches is at Raisby Hill, near Trimdon, 606 feet in elevation, and 17 miles north of the Tees in a direct line. Here rises the Skerne, which flows sluggishly with many windings through the level country past Bradbury and Darlington to Blackwell. Still further east there is a stream similar in character but shorter and smaller, which from Sedgefield runs south-eastward to Norton and Billingham. Between Hartlepool and Sedgefield the level scarcely anywhere exceeds 100 feet, and southward it falls still lower. The streams and ponds of this level low-lying tract furnish the best stations for water-plants which there are in the two counties, as for instance, Morden Carrs, through which the railway runs between Bradbury and Aycliffe Stations, and the streams and ditches about Norton and Billingham. From the Tees mouth at Seaton Carew northward to Hartlepool there is very little cliff along the shore, but from this latter point northward the Magnesian Limestone borders it with fine cliffs in several places, especially at the Black Hall Rocks, and from Horden Dene northward the rocky wall is carried forward almost without interruption. We have regarded the denes of the Magnesian Limestone from Hawthorn Dene southward as comprised in this drainage tract. The most considerable of these is Castle Eden Dene, a thickly-wooded picturesque craggy ravine which extends from the shore midway between Hartlepool and Sunderland for a distance of five miles due west into the heart of the Magnesian Limestone range. The hills round the upper part are from 400 to 500 feet above sea-level. Hesleden Dene, a similar glen a short distance to the south, is about the same length but narrower. Hawthorn and Horden Denes, nearer Sunderland, are both much smaller and shorter. The area of the district is about 300 square miles.
ALTITUDES.
| FEET. | FEET. | |||
| Highfield, above Grasshill | 2322* | Langdon Bridge | 1255 | |
| Fendrich Hill | 2284* | High Force Fall | 942-1005 | |
| Monk's Moor, above Middleton | 1954* | High Force Inn | 1050 | |
| Raven Seat | 1927* | Winch Bridge | 856* | |
| James's Hill, Newbiggin | 2215* | Middleton Bridge over Tees | 729* | |
| Outberry Plain | 2142* | Middleton Bridge Middleton Beck | 765 | |
| Widdy Bank Fell | 1660 | Junction of Middleton and Hamsterley with Barnard Castle Road | 1025 | |
| Widdy Bank Farm-house | 1286 | |||
| Caldron Snout | 1430-1530 |
- ↑ Sopwith "On the Mining District," p. 4.
- ↑ Sedgwick; Trans, of Geological Society, Vol. III, Part 1, 1829; King's Monograph of Permian Fossils. 1848: Howse on the Permian System, in Annals of Nat. Hist., 1857.
- ↑ Trans. Nat. Hist. Soc. of Northumberland, &c. Vol. I, p. 58.
- ↑ Thurmann. Essai de phytostatique applique a la chaine du Jura. Berne, 1849.
- ↑ Cybele Britannica; or British Plants and their Geographical Relations, in four Vols. London: Longmanns, 1847-1859.
- ↑ Geographic Botaniqne raisonnee, on exposition des fails principalis et des lois concernant la distribution geographique des plantes de l'epoque actuelle, par M. Alph. De Candolle 2 Vols. Paris : Masson, 1855.
- ↑ An Essay on the Geographical Distribution of Plants through the Counties of Northumberland, Cumberland, and Durham, by N. J. Winch. Newcastle, 1825.
- ↑ Mr. Watson, in Cybele Britannica, divides Britain into one hundred and twelve of these vice-counties.
- ↑ By Mr. Tate.
- ↑ We may remark in passing, that an idea which we found generally diffused, even amongst educated people, that the little inn at the top of Kirkstone Pass is the highest inhabited house in England, is quite incorrect. The height of this is 1473 feet, and there are dozens of houses higher through the east side of the North of England.