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BATH-CHAIR—BÁTHORY

have been built here. In 1905 three-fourths of the city’s wage-earners were employed in this industry. Bath also manufactures lumber, iron and brass goods, and has a considerable trade in ice, coal, lumber and iron and steel. First settled about 1660, Bath was a part of Georgetown until 1781, when it was incorporated as a separate town; in 1789 it was made a port of entry, and in 1847 was chartered as a city.


BATH-CHAIR, a vehicle with a folding hood, which can be used open or closed, and a glass front, mounted on three or four wheels and drawn or pushed by hand. If required to be drawn by a donkey or small pony it is then mounted on four wheels, with the usual turning arrangement. James Heath, of Bath, who flourished rather before the middle of the 18th century, was the inventor.



BATHGATE, a municipal and police burgh of Linlithgowshire, Scotland, 19 m. W. by S. of Edinburgh by the North British railway. Pop. (1901) 7549. The district is rich in limestone, coal, ironstone, shale and fireclay, all of which are worked. Silver also was once mined. The manufactures include paraffin, paper, glass, chemicals, flour and whisky, and freestone is quarried. The burgh is a considerable centre for agricultural produce. Bathgate became a burgh of barony in 1824 and a police burgh in 1865. Although it was not until the development of its mineral wealth that it attained to commercial importance, it is a place of some antiquity, and formed the dowry of Marjory, Robert Bruce’s daughter, who married Walter, the hereditary steward of Scotland, in 1315.


BATHOLITE (from Gr. βοθύς, deep, and λιθός, a stone), in geology, a term given to certain intrusive rock masses. Especially in districts which are composed principally of rocks belonging to the older geological systems extensive areas of granite frequently occur. By their relations to the strata around them, it is clear that these granites have been forced into their present positions in a liquid state, and under great pressure. The bedding planes of stratified rocks are wedged apart and tongues of granite have been injected into them, while cracks have been opened up and filled with intrusions in the shape of igneous veins. Great masses of the strata which the granite has invaded are often floated off, and are found lying in the heart of the granite much altered by the heat to which they have been exposed, and traversed by the igneous rock in ramifying threads. Such granite intrusions are generally known as bosses from their rounded surfaces, and the frequency with which they form flattish dome-shaped hills, rising above the older rocks surrounding them. At one time many geologists held that in certain situations the granite had arisen from the complete fusion and transformation of the stratified rocks over a limited area of intense metamorphism. The chemical no less than the structural relations of the two sets of rocks, however, preclude the acceptance of this hypothesis. Obviously the granite is an intruder which has welled up from below, and has cooled gradually, and solidified in its present situation.

Regarding the mechanism of this process there are two theories which hold the field, each having a large number of supporters. One school considers that they are mostly “batholites” or conical masses rising from great depths and eating up the strata which lie above and around them. The frequency of inclusions of the surrounding rocks, their rounded shapes indicating that they have been partly dissolved by the igneous magma, the intense alteration which they have undergone pointing to a state approaching actual fusion, the extensive changes induced in the rocks which adjoin the granite, the abundance of veins, and the unusual modifications of the granite which occur where it comes in contact with the adjacent strata, are adduced as evidence that there has been absorption and digestion of the country rock by the intrusive mass. These views are in favour especially in France; and instances are cited in which as the margins of the granite are approached diorites and other rocks make their appearance, which are ascribed to the effect which admixture with dissolved sedimentary material has had on the composition of the granite magma; at the same time the schists have been permeated with felspar from the igneous rocks, and are said to have been felspathized.

The opponents of this theory hold these granitic masses to be “laccolites” (Gr. λάκκος, a cistern), or great cake-shaped injections of molten rock, which have been pressed from below into planes of weakness in the upper portions of the earth’s crust, taking the lines of least resistance, and owing their shape to the varying flexibility of the strata they penetrated. The modifications of the granite are ascribed to magmatic segregation (chemical and physical processes which occasioned diffusion of certain components towards the cooling surfaces). Absorption of country rock is held to be unimportant in amount, and insufficient to account for the great spaces in the schists which are occupied by the granite. Those who support this theory leave the question of the ultimate source of the granite unanswered, but consider that it is of deep-seated origin, and the bosses which now appear at the surface are only comparatively superficial manifestations.

The bulk of the evidence is in favour of the laccolitic theory; in fact it has been clearly demonstrated in many important cases. Still it is equally clear that many granites are not merely passive injections, but have assimilated much foreign rock. Possibly much depends on the chemical composition of the respective masses, and on the depths and temperatures at which the intrusion took place. Increase of pressure and of temperature, which we know to take place at great depths, would stimulate resorption of sedimentary material, and by retarding cooling would allow time for dissolved foreign substances to diffuse widely through the magma.  (J. S. F.) 


BATHONIAN SERIES, in geology. The typical Bathonian is the Great Oolite series of England, and the name was derived from the “Bath Oolite,” so extensively mined and quarried in the vicinity of that city, where the principal strata were first studied by W. Smith. The term was first used by J. d’Omalius d’Halloy in 1843 (Precis Geol.) as a synonym for “Dogger”; but it was limited in 1849 by A. d’Orbigny (Pal. Franc. Jur. i. p. 607). In 1864 Mayer-Eymar (Tabl. Synchron.) used the word “Bathien” = Bajocian + Bathonian (sen. str.). According to English practice, the Bathonian includes the following formations in descending order: Cornbrash, Forest Marble with Bradford Clay, Great or Bath Oolite, Stonesfield Slate and Fullers’ Earth. (The Fullers’ Earth is sometimes regarded as constituting a separate stage, the “Fullonian.”) The “Bathonien” of some French geologists differs from the English Bathonian in that it includes at the base the zone of the ammonite Parkinsonia Parkinsoni, which in England is placed at the summit of the Inferior Oolite. The Bathonian is the equivalent of the upper part of the “Dogger” (Middle Jurassic) of Germany, or to the base of the Upper Brown Jura (substage “E” of Quenstedt).

Rocks of Bathonian age are well developed in Europe: in the N.W. and S.W. oolite limestones are characteristically associated with coral-bearing, crinoidal and other varieties, and with certain beds of clay. In the N. and N.E., Russia, &c., clays, sandstones and ferruginous oolites prevail, some of the last being exploited for iron. They occur also in the extreme north of America and in the Arctic regions, Greenland, Franz Josef Land, &c.; in Africa, Algeria, German East Africa, Madagascar and near the Cape (Enon Beds); in India, Rajputana and Gulf of Cutch, and in South America.

The well-known Caen stone of Normandy and “Hauptrogenstein” of Swabia, as well as the “Eisenkalk” of N.W. Germany, and “Klaus-Schichten” of the Austrian Alps, are of Bathonian age.

For a general account, see A. de Lapparent, Traité de géologie (5th ed., 1906), vol. ii.; see also the article Jurassic. (J. A. H.) 


BÁTHORY, SIGISMUND (Zsigmond), (1572–1613), prince of Transylvania, was the son of Christopher, prince of Transylvania, and Elizabeth Bocskay, and nephew of the great Stephen Báthory. He was elected prince in his father’s lifetime, but being quite young at his father’s death (1581), the government was entrusted to a regency. In 1588 he attained his majority, and,