Page:Encyclopædia Britannica, Ninth Edition, v. 16.djvu/458

Rh 440 M I N M I N the Kenaissance. Early in the century there arose a taste for older models. As, for their writing and afterwards for their printing, they went back to the llth and 12th centuries for their standards, so they adopted again the interlacing designs of the Lombardic school for their orna ment, and produced beautiful borders of twining patterns relieved by colour ; or they took natural objects for their models, and painted borders of delicate flowers made still more brilliant with clustering stars of gold. Later, they drew from the ancient classical designs inspiration for the wonderful borders of arabesques, medallions, griffins, human forms, antique objects, &c., which they brought to such perfection early in the next century. Their miniatures rose to the rank of exquisitely finished pictures, and were executed by some of the best artists working under the patronage of such great houses as those of Sforza and Medici. Here then, having advanced to the threshold of the domain of modern painting, we leave these two great schools of miniaturists in possession of the west of Europe. The Flemings had the wider field ; they were wanderers from home ; and their works are scattered through many lands, from England in the north to Spain in the south. But Italian art had greater inherent strength, and will always hold the first rank. To instance a few of the more famous MSS. of this closing period of miniature painting : the Breviary of Isabella the Catholic, in the British Museum, is a masterpiece of Flemish art produced in Spain ; the Grimani Breviary at Venice is another fine example of the same school. Some beautiful Italian miniatures (executed for Leo X. and others) were in the collection lately sold by the duke of Hamilton. The earl of Ashburnham possesses a most delicately illuminated Book of Hours written for Lorenzo dei Medici by the famous scribe Sinibaldo in 1485, as well as a MS. to which Perugino and his contemporaries contributed paintings. And in one MS., a Book of Hours belonging to Mr Malcolm of Poltalloch, are gathered some of the best miniatures of both schools, viz., a series of exquisite paintings by Milanese artists supplemented by later ones of the finest Flemish type. (E. M. T.) MINIMS. See FRANCIS (Si) OF PAOLA, vol. ix. p. 695. MINING rilHE art of mining consists of those processes by which I useful minerals are obtained from the earth s crust. This definition is wider than what is popularly known as mining, for it includes not only underground excavations but also open workings ; at the same time it excludes under ground workings which are simply used for passages, such as railway tunnels and sewers, and galleries for military purposes. We must remark also that the word &quot; mine,&quot; or its equivalent in other languages, varies in signification in different countries on account of legal enactments or decisions which define it. Thus, in France and Belgium, the workings for mineral are classified by the law of 1810, according to the nature of the substance wrought, into mines, minieres, et carrieres. In the United Kingdom, on the contrary, it is the nature of the excavation which decides the question for certain legislative purposes, and the term mine is restricted to workings which are carried on underground by artificial light. The consequence is that what is merely an underground stone quarry in France becomes a true mine in England, whilst the open workings for iron ore, such as exist in Northampton shire, would be true mines under the French law. It is necessary, therefore, in an article on mining, to go beyond the English legal definition of a mine, and include the methods of working minerals in excavations open to day light as well as in thoss which are purely subterranean. Furthermore, as it is customary for the miner to cleanse his ore to a greater or less extent before selling it to the smelter, we shall treat, under the head of mining, those processes which are commonly known as the dressing or mechanical preparation of ores ; and, finally, a few remarks will be made concerning legislation affecting mines in the United Kingdom, accidents in mines, and the production of the useful minerals in various parts of the globe. The subject therefore will be dealt with as follows : 1. Manner in which the useful minerals occur in the earth s crust, viz., tabular deposits and masses ; faults or dislocations. 2. Prospecting, or search for mineral. 3. Boring with rods and ropes ; diamond drill. 4. Breaking ground ; tools employed ; blasting by vari ous methods ; machine drills ; driving levels and sinking shafts. 5. Principles of employment of mining labour. 6. Means of securing excavations by timber or masonry. 7. Exploitation, or the working away of strata or veins. 8. Carriage or transport of minerals through under ground roads. 9. Winding, or raising in the shafts, with the machinery and apparatus required. 10. Drainage of mines, adit-levels, pumps, pumping engines. 11. Ventilation and lighting of mines. 12. Means of descending into and ascending from mines. 13. Dressing or mechanical preparation of minerals. 14. Recent legislation affecting mines in the United Kingdom. 15. Accidents in mines. 16. Useful minerals produced in various parts of the globe. 1. Manner in which the Useful Minerals Occur. The repositories of the useful minerals may be classified accord ing to their shape as (A) tabular deposits, and (B) masses. A. Tabular Deposits. These are deposits which have a more or less flattened or sheet-like form. They may be divided, according to their origin, into (1) beds or strata, and (2) mineral veins or lodes. (1) .Beds. Geology teaches us that a large proportion stratified of the rocks met with at the surface of the earth consist deposits. of substances arranged in distinct layers, owing to the fact that these rocks have been formed at the bottom of seas, lakes, or rivers by the gradual deposition of sediment, by precipitation from solutions, and by the growth or accumu lation of animal and vegetable organisms. If any one of these layers consists of a useful mineral, or contains enough to make it valuable, we say that we have a deposit in the form of a bed, stratum, or seam. Of course the most important of all bedded or stratified deposits is coal, but, in addition, we have beds of anthracite, lignite, iron ore, especially in the Oolitic rocks, cupriferous shale, lead- bearing sandstone, silver-bearing sandstone, diamond-, gold-, and tin-bearing gravels, to say nothing of sulphur, rock-salt, clays, various kinds of stone, such as limestone and gypsum, oil-shale, alum-shale, and slate. The characteristic feature of a bed is that it is a member of a series of stratified rocks ; the layer above it is called the roof of the deposit, and the one below it is the floor. Its thickness is the distance from the roof to the floor at right angles to the planes of stratification ; its dip is the