Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/457

CORNWALL 42, even apples and pears, do not attain the same full flavour as in the neighbouring county, owing to the want of dry heat. The pinaster, the Pinus austriaca, Finns imignis, and other firs succeed well in the western part of the county. All native plants display a perfection of beauty hardly to be seen elsewhere, and the furze, including the double blossomed variety, and the heaths, among which Erica vagans and ciliaris are peculiar to Cornwall, cover the moorland and the cliff summits with a blaze of the richest colour. On the whole the climate is healthy, though the constant west and south-west winds, bringing with them great bodies of cloud from the Atlantic, render it damp and showery. Agriculture has not received so much attention here as the more remunerative although more speculative pursuit of mining. Barley, wheat, and oats are the principal corn crops, and the acreage under each of these is much the same in amount ; while of green crops one-half the acreage is occupied by turnips, a fifth by mangolds, and only a tenth by potatoes. Early potatoes, brocoli, and asparagus are grown extensively around. Penzance, where the climate is very equable, and these products are sent off in large quantities to the London market. The stock of animals is considerable, and has recently been increased to some extent. The cattle, which on some farms are used for ploughing, belong mostly to the Devon breed. The following tables, taken from the agricultural returns, show the acreage of crops and numbers of live stock in the years 1873 and 1876 respectively: Acres Percentage unae,corn Green crop, Bunder of are* cr P s - cultivation. 1873 150,106 60,244 149,785 59 1876 143,211 60,281 138,721 60 Cattle. 145,286 155,950 Sliccp. 408,173 437,440 Pigs. 62,827 62,206 Horses. 37,466 30,613 With reference to the division of the land, according to the "Owners of Land" Return, 1873, the county was in that year divided among 13,8GG separate proprietors, holding laud estimated at a total value of 1,235,107. There were 8717 owners of less than 1 acre, and the largest separate property amounted to 25,9 10 acres. Of the whole proprietors 62 per cent, held less than 1 acre of land, which is a little under the proportion of small proprietors in the neighbouring county of Devon, and still more under that of all England. The average size of the properties was 54 acres, while that of all England was 34, and the average value par acre was l, 12s. G.kl. as against 3 the average L O O of the whole country. The proprietors who in 1873 held more than 10,000 acres in the county were the following: Viscount Falmouth, 25,910; Lord Robartes (Lanhydrock), 22,234; Hon. G. M. Fortescue (Boconnoc), 17,208; G. L. Bassett (Tehidy Park), 16,969; Earl of Mount Edgcumbe, 13,283; Duchy of Cornwall, 12,516; C. H. T. Hawkins (Probus), 12,119; and Lord John Thynne, 10,244. Economic Geology and Mines. The granite, the slate, and the serpentine of Cornwall are of the first importance. The mines are amo:ig the chief features of the county. Granite is largely quarried in various districts, especially at Luxulian, on the Liskeard moors, and at Penryn, and has served for the material of London and Waterloo bridges, the docks of Chatham, and many great public works. The granite of Cornwall is for the most part coarse-grained ; but in this respect it differs considerably in different places, and the coarse-grained rock is often traversed by veins of finer texture. From the Delibole quarries, in the Devonian series, near Tintagel, tha best slate in the kingdom is extracted, and is largely exported; 120 tons are raised on an average daily. These slates were in great repute in the 16th century and earlier. Serpentine is quarried in the Lizard district, where alone it is found, and, besides its use as a decorative stone, it is exported in small quantities to Bristol for the manufacture of carbonate of magnesia. China-clay is prepared artificially from decomposed granite, chiefly in the neighbourhood of St Austell, and is exported to an annual amount of about 80,000 tons. The chief mineral productions of Cornwall, considered as objects of trade, are tin and copper, the former being found nowhere in the United Kingdom except in Cornwall and Devon. Both these metals occur most plentifully in the Devonian series, but for the most part in the neighbourhood of granite, or of its modification, elvari. The veins of ore are arranged in groups as follows : 1. That of St Austell, chiefly stanni ferous ; 2. St .Agnes, chiefly stanniferous ; 3. Gwennap, Redruth, and Camborne, chiefly cupriferous; 4. "Breage, Marazion, and Gwinear, of mixed character ; 5. St Just and St Ives, mainly stanniferous. Besides tin and copper, anti mony ores are found where the Devonian rocks are much traversed by traps, as at Endellyon, Port Isaac, and St Germans. Manganese is also found under similar condi tions. Some lead occurs, and some small mines are worked, but with no great results ; and iron, in lodes, n.s brown haematite, has been worked extensively near Lost- withiel and elsewhere. Metals occur in the lines of fault and fissure, which extend through the different geological formations of Devon and Cornwall. In Devon and in East Cornwall these lines run nearly IS", and S., and are crossed by others running E. and W. In West Cornwall the lines are more bent, and the main fissures take a direction nearly parallel with the general range of land. Metallic fissures are locally termed lodes. Ores are not disseminated through all parts of the fissures in which they are found, but are gathered in patches known as " bunches of ore," the intervening portions containing strings and specks of metal, but in quantities too small to be profitably worked. It should be observed that in all lodes or fissures, whatever may be the nature of their produce, the parts most highly inclined are always the most productive. Tin occurs not only in lodes but in streams of stones and minute grains, carried from the head of the lode, where it neared the surface, apparently by some great force of water, which must have rushed from N. to S., since the great streams of tin are in all instances carried toward the S. coast. Stream tin is found immediately on the hard rocky surface of the country, and is covered by numerous tertiary deposits, which indicate that much of the coast line has been depressed and again raised, since the first deposit of the tin stones. Oxide of tin also generally occurs in the " gossan," or ochreous substance which forms the upper part of a good copper lode. The native ore from the mine or the stream-work is known as black tin. White tin is the metal after smelting. In the stream works tin pebbles are sometimes found of 10 or 12 Tb weight, and great masses of rock richly impregnated with metal have occurred weighing more than 200 Ib. But the small or grain tin, as it is called, is of better quality. Tin occurs in both granite and slate ; copper for the most part in granite. The most important Cornish copper ore is the sulphuret, commonly known as grey ore by the miners ; but copper pyrites, or the bisulphuret of copper, occurs far more frequently in both Cornwall and Devon. The tin of Cornwall has been known and worked from a period long before the dawn of certain history. Copper, which lies deeper in the earth, and consequently cannot be " streamed" for, was almost unnoticed in the county until the end of the 15th century, .and little attention was paid to it until the last years of the 17th. No mine seems to have been worked exclusively for copper before the year

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