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 chancel, a magnificent rood-loft, and a 13th-century monument doubtfully described as the tomb of Bracton, the famous lawyer, whose birthplace, according to local tradition, was Bratton Court in the vicinity. Coaches for Porlock and Lynton start from the town.

There is no evidence of the existence of Minehead (Mannheve, Manehafd, Mynneheved) in Roman or Saxon times. The town owed its origin and growth to its position on the shores of the Bristol Channel, and its good harbour developed an oversea trade with Bristol, South Wales and the Irish ports. The De Mohun family were overlords of the town from 1086 to the 14th century, when they were followed by the Luttrells, who are the present owners. It is possible that Minehead had a corporate existence during the 15th century, as certain documents executed by the portreeve and burgesses at that date are preserved, but no record of the grant of a charter has been found. A charter of incorporation given by Elizabeth in 1558 vested the government in a portreeve, a steward and twelve burgesses, the continuance of the corporation being subject to the port and harbour being kept in repair. This condition being unfulfilled, the charter lapsed in the reign of James I., and an attempt to obtain its renewal in the 18th century failed. The corporation was replaced by two constables chosen annually in the court leet of the manor until 1894, when an urban district council was appointed. The borough returned two members to parliament from 1558 until disfranchised by the Reform Act of 1832. A weekly market on Tuesdays and a fair (Sept. 29 to Oct. 2) were held by the lord of the manor from the 15th century, but the date of the grant has not been found. In 1465 a second annual fair on the 1st of May was granted by Edward IV., which is still held on the Wednesday in Whitsun week. The other fair has been discontinued, and the market day has been changed to Wednesday. During the 16th, 17th and 18th centuries Minehead had a considerable coastwise trade in wool, grain and wine, but began to decline owing to the migration of the woollen industry to the north of England, and to the decay of the herring fishery. A renewal of prosperity began when it acquired a reputation as a watering-place.

 MINEO, a town of the province of Catania, Sicily, 34 m. S.W. of Catania by rail. Pop. (1901), 9828. It occupies the site of the ancient Menaenum, founded by Ducetius in 459 There is some doubt as to whether this town was also the birthplace of Ducetius, owing to confusions in nomenclature (see E. A. Freeman, History of Sicily, ii. 361). Remains of fortifications still exist, though it seems uncertain whether they are of Greek or of Byzantine origin (Notizie degli Scavi, 1899, p. 70). Four miles to the north is the Lacus Palicorum, a small lake in a crater, which still sends up carbonic acid gas. By it was the temple of the Palici, twin Sicel gods, the most holy place in Sicily, where an oath taken was especially binding, and an inviolable asylum for fugitive slaves. There is now nothing to suggest twin deities; in ancient times there were probably two craters, whereas now there is only one. It was here that Ducetius, a few years later, founded a new seat for his power, the city of Palica.  MINERAL DEPOSITS. The subject of (q.v.) can only be properly understood after the general features of mineral deposits have been elucidated. In this article deposits of all kinds of useful minerals are included, whether they are metalliferous or earthy. In general practice it is customary to treat the former under the name “ore-deposits” and the latter as the “non-metallics.” This is warranted because in a large degree different geological problems are presented and different methods of mining are pursued. Nevertheless there are other important similar or common features and they may be classed together without great disadvantage.

The word “ore” is used in several meanings, each of which depends for its special significance upon the connexion. In purely scientific applications “ore” implies simply a metalliferous mineral, and in this sense it appears in works on mineralogy and petrology. In former years and in

connexion with practical mining an ore was defined as a compound of metal or of metals with one or more non-metallic elements, called mineralizers, of which oxygen and sulphur were the chief. The ore must, in addition, be sufficiently rich to be mined at a profit. Native metals not being compounds were not considered ores. The product of the copper mines on Keweenaw Point, Lake Superior, was, and to a great extent is still, called copper rock rather than copper ore, and native gold in quartz is often described as gold quartz rather than gold ore, but these restrictions are gradually disappearing. An ore may therefore be defined as a metalliferous mineral or aggregate of metalliferous minerals mingled with a greater or less amount of barren materials called the “gangue,” and yet rich enough to be mined at a profit. When not proved to be sufficiently rich to be remunerative, the aggregate is called “mineral.” The “mineral” of to-day may be changed by the advent of a railway or the rise in the price of metal into the “ore” of to-morrow. The question has repeatedly appeared in litigation involving contracts or property rights.

Since the greater number of the ores are believed to have been precipitated from aqueous solution, or to have been otherwise formed through the agency of water, the term “ore-deposit” has resulted; and inasmuch as nearly all the other useful minerals owe their origin to the same agent, the term “mineral deposit” is equally well justified. A few, however, have been produced in a different way, such as certain iron ores of igneous origin; certain igneous rocks used for building stone, as in the case of granite; and the accumulations of vegetable material in coal beds. These latter, the igneous masses and the vegetable, accumulations, being placed in two divisions by themselves, we may group the larger number into two main classes, depending on their precipitation from solution or from suspension. In the case of solution we will further subdivide on the place, and therefore in large part on the cause, of precipitation, since these are the questions chiefly involved in actual development.

Especially in connexion with ore-deposits widening experience has modified the older conceptions of relative values in the several types. In the early days of geology, Cornwall and Saxony were the two regions where the most active and influential students of ore-deposits were trained and where the principal books relating to mining originated. The pronounced and characteristic fissure veins of England and Germany became the standards to which the phenomena met elsewhere were referred, and by means of which they were described. This particular form, the fissure vein along a fault, assumed a predominating importance, both in the thought and in the literature of the day. Widening experience, however, especially in the Cordilleran region of North America, in the Andes of South America, in Australia and in South Africa, has brought other types into equally great and deserved prominence. Comprehensive treatment to-day therefore departs somewhat from earlier standards.

As far as analyses and estimates permit, the common useful metals occur in the earth’s crust in approximately the following percentages:—

By the letter x is meant some undetermined digit in the corresponding place of decimals. Apart from aluminium, iron, manganese and nickel, the figures show how small is the contribution made by even the commoner metals to that portion of the mass of the globe which is open to observation and investigation.

As compared with the earth’s crust at large certain of the metals are known to be locally present in favourable, usually igneous, rocks in richer amounts, according to the following determinations which have been made upon large, samples of carefully selected materials. Copper, 0·009%; lead, 