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by the Chinese-in fact, when our ancestors were naked savages, the Chinese peasantry were clothed in silk!' From China, the cultivation and manufacture of silk extended to India, and thence was introduced into Europe in the 6th century, gradually spreading westward from Greece to Italy, Spain and France. China still furnishes nearly one-half of the total production of raw silk; Italy, Japan and India produce about one-third of the total quantity; the rest is supplied by Southern Russia, Asia Minor and Persia, Southern France, Austria-Hungary, &c. France is the greatest silk manufacturing country in the world, but the production of raw silk has, since 1856, been greatly diminished by a disease among the worms; to remedy this, new "seed" and other varieties have been introduced from China and the East Indies. Much of the raw silk of India is obtained from the tussar moth, which yields ten times as much silk as the common silkworm, and in China fully one-fourth of the silk is the product of various "wild moths." Honey and Wax are valuable commercial products. Bees' Wax and Honey, though produced in great abundance in all European countries, are largely imported from America, bee-keeping being a leading industry in Californiathe 'paradise of bees '--and some parts of Canada. The lac used in making sealing wax is the product of an Indian insect of the same genus as the little Mexican insect which yields cochineal, a beautiful scarlet dye, now produced chiefly in the Canary Islands. The famous white-wax insect of China gives rise to an extensive industry and a large internal trade.'

Fish constitutes an important article of commerce, furnishing us with an abundance of food, and immense quantities of oil.

The most important, commercially, are the cod, a valuable food-fish (and yielding also the well-known cod-liver oil), widely distributed, especially along the western side of the North Atlantic-the greatest cod-fishery in the world being on the great Banks of Newfoundland; the herring, which appears in vast shoals on our coasts, and supplies an enormous amount of nutritious food; the salmon, caught in great numbers in rivers and estuaries, as well as in bays and the open sea, chiefly on the Pacific coast of North America, where over 26,000 tons of salmon are canned for export every year; the sturgeon of the Black and Caspian Seas, the dried roe of which forms the caviare of commerce, while isinglass is prepared from its air-bladder, and the leather known as shagreen from its skin. The tunny and sardine of the Mediterranean, and the mackerel, haddock, whiting, sole, plaice, turbot, &c., of the British seas, are all important food-fishes, and articles of considerable commerce. into the United Kingdom, Germany, and the United States, but the great Millions of fish are imported bulk of dried and salted fish is sent to the Catholic countries of Europe, chiefly for consumption during Lent. Lobsters, oysters, and other shell-fish are very largely used as food; the oyster is extensively cultivated in the United States Holland, France, &c.

The commercial products of the Mineral Kingdom are numerous and important. Metals and metallic ores, mineral fuels and oil, building-stones, clays and chalks, earths and precious stones, form the chief mineral products.

The study of mineralogy is of the utmost practical value to civilized
that "it tells him how and where to find in the several classes of rocks those
man, in
mineral products so essential to his welfare-the materials used in the
construction, adornment, lighting and heating of his dwellings and factories;

See Hosie's "Three Years in Western China." | of stocking barren waters with valuable food-fishes,
(London: George Philip & Son.)
have appointed commissioners to protect and
has been amply demonstrated, and most countries
develop their fisheries.

2. "The artificial propagation of fishes has become an important industry both in Europe and America. The possibility of successfully hatching ova, and

in the manufacture of his tools and machinery; in the enrichment of exhausted soils; the substances employed in the various arts; the pigments and dyes; the mineral medicines; the precious metals, and the gems."

Iron, the most indispensable of all metals, is also the most abundantly and widely distributed.

Iron is rarely found in a pure state, but iron-ore, that is, iron combined with certain other substances, occurs in one form or another in nearly every part of the world, and in connection with very different formations.

It is within the carboniferous area, however, that iron can be most profitably worked, from the occurrence there, in immediate proximity, of iron, coal, and lime, that is, of the ore, the fuel, and the necessary flux, or medium, for the conversion of the ore into the workable metal." Deposits of iron-ore are thus most readily and largely utilized when found in conjunction with coal. The substances com. bined with the metal in the ore are so far got rid of by smelling (most ores must be roasted first of all) in the blast furnace; the molten metal is then run off into moulds, and takes its first marketable form as pig-iron or cast-iron. Pig-iron, however, still contains some carbon, which renders it very brittle, and suitable only for castings; it is therefore re-melted, and by puddling or stirring the molten metal, nearly all the carbon is driven out, thus forming malleable or wrought iron, which is rolled into bars or sheets, &c. But even wrought iron is not hard or tenacious and flexible enough for many purposes; it is therefore converted into steel by the old process of cementation (which still produces the finest cast steel), or by some cheaper process, such as the Bessemer, SiemensMartin, &c. Bessemer steel cannot be made from iron containing phosphorusa most injurious element in iron, but steel can now be made even from this by what is called the basic process (discovered by two Middlesborough gentlemen, Messrs. Thomas and Gilchrist), with the result that the manufacture of cast steel on a large scale is rapidly extending, and steel is now being largely used instead of wrought iron for almost all purposes.

The Iron industry may be said to be the most essential of all modern industries, very few, if any, of which could be carried on at all without the aid of iron in some form. Great Britain and the United States surpass all other countries in the production and manufacture of iron, Germany and France follow with a production equal to about one-half of the British out-put. Belgium, Sweden, Russia, Austria-Hungary, and other countries, all produce more or less iron or iron-ore. There are abundant deposits of iron-ore in India and many of the British Colonies, but the absence of fuel and of facilities for transport, &c., have prevented their being worked to any extent.

Gold and Silver are of value mainly as Instruments of Exchange, the precious metals, as they are called, forming the standard coinage of all civilized countries.

As iron is the most useful, so gold is the most valuable and highly prized of all metals. Gold is as widely distributed as iron, but more sparingly, occurring in quartz veins or in alluvial deposits in all parts of the world. In alluvial deposits, pure gold is found in pieces or nuggets, varying in weight from a few grains to several pounds, or as dust and 'scales.' In quartz-mining, the gold is obtained by "stamping" or crushing the quartz to powder, which is then washed away with water, "quicksilver being used to combine the fine metallic particles with itself in an 'amalgam.' from which the gold is afterwards separ

ated." Gold is extremely malleable and ductile-it can be hammered or beaten out into leaves of an inch in thickness, and a single grain can be drawn out into a wire 100 yards in length.

The Richest Gold-Fields in the world are in North America, in the region lying between the Pacific coast and the Great Plains. The Australian goldfields rival those of California in richness, and surpass them in extent; and New Zealand and Russia (principally the Ural region and Eastern Siberia) rank high as gold-producing countries. Much gold-dust is exported from tropical Africa, and the new gold-fields in the Transvaal (around Johannesburg and Barberton) and Mashonaland promise to be, when fully developed, among the richest in the world. Mexico, Central America, Brazil, Guiana, and the Andean countries, contain large deposits of gold. The annual production of gold amounts to about 20 millions sterling, of which the United States contribute over 6 millions, Australasia nearly 6 millions, and Russia 4%1⁄2 millions.

Silver is scarcely ever found in a pure state, being generally found in combination with other elements, in fact, nearly one-half the world's production of silver is obtained by the desilverisation of ores worked for lead and copper. The United States produce twice as much silver as Mexico, and three times more than Bolivia. Germany, Chili, Peru, Japan, Austria-Hungary, and Colombia, rank next in importance as silver-producers, but their total yearly production scarcely exceeds 5 millions sterling.

Mercury, or quicksilver, the only metal which is fluid at ordinary temperatures, is used in making scientific instruments (the barometer, &c.), and as an amalgam with tin for silvering mirrors, &c. Quicksilver is also employed for the extraction of silver and gold. The famous mines of Almaden in Spain, and those of Idria in Carniola, supply nearly all the mercury produced in Europe, but they are now surpassed by the celebrated quicksilver mines of New Almaden in California.

Copper is found pure in some localities-native copper is found in huge masses on the northern shores of Lake Superior; but this metal, which is largely used for electrical purposes (telegraph and submarine cable wires, &c.), and as an alloy with tin to make bronze and with zinc to make brass, is principally extracted from ores. Ores of copper sulphide a compound of copper and sulphur-are difficult to reduce, hence large quantities of raw ore and regulus, or partially refined ore, are sent chiefly to Swansea, Widnes, and Glasgow, to be converted into pure copper, the sulphur fumes being caught and used for making sulphuric acid. Chili was formerly the chief copperproducing country; it is now surpassed by the United States and Spain; Germany and South Australia rank next in order. The famous copper-mires of Cornwall are nearly worked out, but British trade in copper is still the largest in the world.

Tin withstands the action of air and water so well that it is chiefly used for coating or tinning sheets of iron, the tin-plate thus formed being very largely used in the fish and fruit 'canning' industries, and for making domestic articles of daily use in all countries. The tin deposits of Cornwall and Devon were worked two or three thousand years ago, and are still productive; but most of the tin of commerce is supplied through Singapore, from the famous mines of Banca and Billiton, in the Dutch East Indies, and the adjoining islands and peninsula of Malaysia. New South Wales and Tasmania yield large supplies, and Bolivia, Peru, Chili, and other countries, possess rich tin ores, but they are not as yet much worked.

oz. to the ton.

Lead, a soft, heavy, and easily fused, but not readily oxidized, metal, is in great demand for making gas and water pipes, shot, and paints. The chief lead ore, galena, a compound of lead and sulphur, usually contains more or less silver, which is extracted when the quantity is not under Spain and the United States, Germany and the United Kingdom, are the chief lead-producing countries-Germany producing twice, and Spain and the United States each three times as much as this country, which, however, has the largest trade in lead.

Other useful metals are :-Zinc, largely used in making brass and coating iron (gal. vanized iron), and produced chiefly in Prussia and Belgium; Platinum, a rare metal, produced chiefly in the Ural region, the heaviest substance known and the most difficult to fuse, hence invaluable for making crucibles, &c.; Nickel, which occurs chiefly in New Caledonia, used in the coinage of the United States and other countries, and for plating steel, and also as an alloy with copper for making German silver. Antimony, bismuth, chromium, arsenic, and especially manganese, now so important in the manufacture of steel, are also of great value in many industries.

Mineral Fuels are indispensable to the commerce and industry of the world.

Coal is a necessity in almost all modern industries of any magnitude, and is in universal demand for household purposes; in fact, of all mineral pro ducts, coal is of the most direct value to civilized man.

So essential an article is, fortunately, widely distributed over the earth, and both anthracite and bituminous coal are supplied in immense quantities from the British, American, and other coalfields, but vast deposits of coal in China and other countries are scarcely worked at all. The annual coal production of the world amounts to over 450,000,000 tons, nearly three-fourths of which is contributed by Europe, one-fourth by the United States, and the rest by Australia, Japan, &c. Four-fifths of the entire quantity are produced by Great Britain, the United States, and Germany. The British coal production is more than a third of the total production of the world, amounting on an average to upwards of 180,000,000 tons. The United States rank next in order with over 160,000,000 tons; Germany comes third with 71,000,000 tons; France produces 26,000,000 tons, Austria-Hungary 21,000,000, and Belgium, 20,000,000. Over 30 million tons of lignite, or brown coal, are produced every year, chiefly in Germany and Austria-Hungary.

AREA OF COALFIELDS AND ANNUAL PROduction of COAL.

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All mineral fuel is composed of carbonised vegetable matter-peat, largely used as fuel where coal is scarce, representing the first stage; lignite, or brown coal, is also a tertiary or geologically recent deposit, and much less ancient than the formations which yield the more or less highly mineralised coals known as anthracite and bituminous coal respectively. Coke is artificially produced from certain kinds of bituminous coal.

The

Mineral Oils, Building Stones, Clay, Salt, and other mineral products, are also of immense value for domestic and manufacturing purposes.

The Petroleum industry of the United States and Trans-Caucasia, especially, is on a large scale, and the trade in petroleum oil and other products has attained enormous dimensions, and rapidly increasing, as these mineral products are fast superseding both vegetable and animal oils for lighting and heating, and as lubricators for machinery and fuel for steam-engines, and for smelting iron and making glass, &c. Some of the wells at Baku, on the Caspian Sea, yield over a million gallons of oil a day, and the great oil region of the United States produces over 2,000 million gallons of oil a year. The crude oil is conveyed in tank waggons or by pipe-lines (some of them hundreds of miles in length) to the refineries at the ports, and thence pumped into tank-steamers for conveyance over sea. The new pipe-line from Baku to the Black Sea, about 600 miles in length, will transmit 1,200,000 gallons of oil a day.

Valuable mineral oils are also produced, but in much smaller quantities, in other countries, such as Galicia and Roumania, in Europe; Canada, Venezuela, the West Indies, &c., in America; China, and especially Burma, in Asia; New South Wales, New Zealand, &c.

Paraffin oil is distilled from bituminous shales in Scotland, France, and New South Wales. The solid paraffin is made into candles. Asphalt, so largely used for paving, is derived from the so-called pitch lake in Trinidad, and is found on the shores of the Dead Sea (hence its ancient name Lacus Asphaltites) and many other localities.

Building Stones: Limestone, sandstone, granite, flag-stones, and slate are extensively used as building stones, and give rise to a large trade, especially in granite from Scotland, slate from Wales, and marble from Italy and other countries. The finest white or statuary marble is quarried at Carrara in the Apennines; the best slate comes from the Penrhyn Quarries in Carnarvonshire; and the most valuable ornamental granites are sent from Aberdeen to all parts of the world.

Common Clay is made into bricks and tiles, common pottery, &c. China and porcelain are made from the fine clays, originally obtained from China, hence called China-clay (kaolin). Fire-clay, employed for making crucibles, firebricks, &c.; lime, used for mortar, or as a fertilizer; cement, an impervious mortar; sand, used in making mortar and glass; and lithographic stones, &c., and other useful mineral products are in constant demand in all civilized countries.

Salt, one of the most essential commodities, is abundantly distributed. There are mines of rock-salt in the Weaver valley in Cheshire; and the famous salt mines of Wieliczka, near Cracow, contain miles of galleries, dazzlingly white buildings, churches, &c., all cut out of solid rock-salt. Brine springs and seawater yield enormous supplies by evaporation. The United Kingdom produces and consumes more salt than any other country, the annual yield being over 2% million tons, of which a large proportion is exported principally to India and the United States. Immense deposits of Nitrate of Soda or Cubic Nitre are found in Chili and Peru; over two million tons are annually exported to Europe for use as a mineral manure, and in certain chemical industries. Borax is found in countries with very dry climates, such as Tibet, California and Nevada in the United States, and Peru; it is also obtained by evaporation from the volcanic lagoons of Tuscany.

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