Achievements Of The 19th Century:
A Century Of Achievement
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Mining And Metallurgy
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Mining And Metallurgy
( Originally Published Early 1900's )
Mining and metallurgy are not devices of the Nineteenth Century; for Tubal Cain is mentioned in Genesis as a worker in metals, and ever since then men have dug minerals from the earth and fashioned them to their uses. Yet because of improved methods in digging out subterranean treasures and extracting the ores, the industries of mining and metallurgy have had a phenomenal growth during the past hundred years. While agriculture has only doubled and manufactures quadrupled since 1840, the mining output has increased thirteen-fold. The increase since 1840 is shown by the following table, compiled by the statistician Mulhall:
Hands. Tons raised. Value.
1840 442,000 56,200,000 $157,500,000
These statistics show that, although mines are deeper, one man now raises as much weight in mineral wealth to the surface of the earth as two did fifty years ago. It is worth mentioning that the United States mines about one-third, Great Britain one-third, and the rest of the world combined the other third in quantity, while in value the United States is far ahead.
Seventy per cent of the total weight of minerals mined is coal, and so in a review of the gigantic and marvelous developments that have taken place in mining and metallurgy during the Century just closing, too much importance cannot be attached to that mineral, as the chrysalis of latent energy, as the one great omnipotent factor of all modern industrial evolution. Indeed, so all-essential has coal become to civilization, that man dare not even in fancy conceive of a time when it shall have become exhausted. Yet the geologist and the statistician have logically demonstrated that at the present rate of consumption the coal supply of the entire world will have been consumed within one thousand years. In answer to the question that naturally arises, What then? scientists, philosophers and magicians are all mute; for, so far as they are now able to see, all their vaunted triumphs will be as naught on that fatal day, and the wheels of progress forever cease to turn.
Yet the grimy black substance which we have come to regard as an absolute necessity to our very existence, was practically unknown to our forefathers except as an obnoxious and unwelcome substitute for fire-wood. The opening of the present century found the world in comparative ignorance of its industrial value.
The first authentic mention made of coal in history is by Theophrastus, about 300 B. C., although it is probable that its combustible qualities were discovered long before that. It was mined by the men of the paleolithic and neolithic ages, as we know from the flint axes and other implements found in prehistoric excavations in various parts of England. It is possible that the early Britons were slightly acquainted with its industrial value at the time of the Roman invasion in 55 B. C. In 1239 a char-ter was granted the freemen of Newcastle, giving them permission to dig and gather coal in the Castle fields, and here the history of coal as a commercial product may be said to have begun. When Newcastle coal was offered for sale in London it was indignantly rejected by the city fathers as an innovation inimical to the health and happiness of the city, and it was not until after much persuasion that permission was given to unload it. In 1300 a proclamation was issued by the King, prohibiting its use within the city walls, and imposing a fine upon those who persisted in burning it. The license granted the freemen of Newcastle was revoked, and the coal question was sup-posed to have been settled forever. During the reign of Edward III, the prohibitive law was repealed and the New-castle freemen were again allowed to dig and gather coals and ship them to London. During the reign of Elizabeth its use was again prohibited in London during the sitting of parliament, as it was claimed to be injurious to the health of the country squires during their sojourn in the city. But notwithstanding the many obstacles placed in the course of its progress, the use of coal spread rapidly, and the middle of the last Century found it used almost exclusively in the smelting of iron and for other industrial purposes all over England.
Although the early history of coal is thus distinctly linked with the history of England, its later history is common to nearly all the great nations of the world.
The first discovery of coal in America was made at Ottawa, Illinois, as is chronicled by Father Hennepin, a Jesuit explorer, who visited that section in 1679. The first coal mine was excavated near Richmond, Virginia, the discovery having been made by a small boy while fishing on the James River, the bituminous vein being exposed along the shores of the stream. Ten years later the famous strata of bituminous coal was discovered around Pittsburg, and at the beginning of the Nineteenth Century shipments were made to Philadelphia. Anthracite coal was discovered by a hunter, Nicho Allen, near Wilkesbarre, Pa., in 1792. Like many other important discoveries, it was accidental. Allen encamped one night and built his fire upon some small black stones that lay scattered about in profusion. Having cooked his supper, he went to sleep as usual, and when he awoke in the middle of the night he found himself lying in a bed of flames. The stones were all on fire, and he barely escaped with his life. He told the story of his adventure far and wide, and shortly afterwards a company was organized to mine and ship the black stones to Philadelphia. Colonel Shoemaker, a worthy colonial gentleman, was at the head of the enter-prise, and upon his recommendation most of the first consignment was sold. The people, however, did not understand how to use the coal, and there was a popular feeling of indignation against Colonel Shoemaker, who was denounced by the city authorities as a rascal for having palmed off rocks upon them as coal. Since then Philadelphia has grown to be a great city largely through the agency of those same black rocks, and the anthracite coal fields of Pennsylvania yield 50,000,000 tons annually.
It would be hard to estimate the amount of money the United States has made out of its coal. One small region in Eastern Pennsylvania produces every year coal to a greater value than all the gold mines of the Rockies, Canada and Alaska. Adding to this the value of our annual production of a hundred and thirty odd million tons of bituminous coal, it can be said safely that we get more than three times as much wealth out of our coal mines as out of our gold mines. The great Appalachian field produces I00,000,000 tons annually. Indiana, Kentucky and Illinois have an immense output. Utah, Montana, Colorado, Washington and Wyoming are also rich in coal deposits, and fields of incalculable value have been in late years discovered in Alaska. There is scarcely a country on. earth where coal has not been discovered in greater or less quantities. The following table is the latest estimate (1897) of geologists regarding the world's coal producing territory : China, 200,000 square miles; United States, east of the Rockies, 192,000 square miles; Canada, 65,000; India, 35,000; New South Wales, 24,000; Russia, 20,000; United Kingdom, 11,500; Spain, 5,500; Japan, 5,000; France, 2,080; Austria-Hungary, 1,790; Germany, 1,770; Belgium, 510.
Although the English coal area is comparatively small, nevertheless that country was for years the center of the coal production of the world, and for many years mined more than half the total amount used by the world. But her coal production is being gradually overshadowed by that of the United States. The English coal veins are shallow. The Newcastle coal fields, her richest, have veins from three to six feet thick, while the Pennsylvania anthracite veins run from thirty to sixty feet in thickness, and the Pittsburg bituminous veins from ten to sixteen feet. Some of the English veins are already worked down 3,887 feet, and at the present rate of mining it is estimated that if it is worked down to 4,000 feet English coal will be exhausted in about 200 years. It is therefore possible that England's glory as a manufacturing nation must soon be on the wane. It is also self-evident that the United States, with its vast supplies of that mineral, and its magnificent facilities for transportation, already the chief manufacturing nation of the world, is destined to increase its lead enormously. The coal mining systems perfected during the present Century, and their equipments of colossal machinery are among the wonders of the engineering and mechanical world. The modern coal mine of a large scale is really an underground city with avenues and streets extending for many miles. One of the largest of these subterranean towns is near Newcastle, England, and contains not less than fifty miles of passages, the result of excavations wrought by human hands.
The mode of working the coal mines has undergone a complete revolution. The older process was, after reaching the strata to be operated, to take out as much of the material in stalls as was considered safe. This left a pillar to support the roof of the mine, and thus only a portion of the material was available. In 1816, by the introduction of the Davy Safety lamp, it was rendered possible to work in what were very dangerous circumstances, and less and less wall was left in the form of pillars. This was called the "long wall working," and is the method in use at the present day. The system consists in the excavating first of long roadways through the strata, the superincumbent strata sinking down on the top of the wastes left behind by the miners.
The ventilation of mines had long engrossed the attention of engineers and legislatures. The first radical improvement brought about in this direction occurred in the year 1820, when the workings were divided into distinct portions or panels so as to insure a direct passage of air from the downcast to the upcast shaft. These shafts are, in reality, very deep wells sunk at either end of the mine. The air from the downcast rushes through the passage and seeks egress by way of the upcast. The draught of air thus created, while it carried away a certain amount of impurities, was insufficient to provide air for inhalation by the army of workers. To accomplish this a large furnace was placed at the foot of the upcast shaft. the intense heat arising from this furnace rarified the column of foul air admitted above it, thus causing it to ascend and make room for the colder air from the down-cast shaft. For many years this method was without a rival. Various pumps, fans and pneumatic screws were tried without success. But in 1849 an English mine owner named Powell put into his mine a large centrifugal fan, designed by Brunton. It operated on a vertical axis and was placed at the surface. Although it was a marked improvement on the old furnace system, the new ventilator made slow progress until Guibal introduced another large fan at the London Exhibition. Since then the many advantages to be derived from mechanical means of ventilation at the surface have become more fully recognized, and fans, some of which run at terrific speed, are in use at all modern collieries.
The haulage of coal from the diggings through the devious passages to the foot of the mine shaft is another item in coal mining which has been greatly improved. The use of cast iron tramways dates back to 1767, and about 1820 George Stephenson introduced mechanical haulage underground, although its success was not ultimate until the use of wire ropes became general. Until 1845, or thereabouts, the underground haulage was accomplished chiefly by women and children, who were treated by their overseers as veritable beasts of burden. The passage of legislative acts about this time compelled proprietors to use ponies and horses underground. For many years chains and ropes were used for mechanical hauling and winding, a practice which entailed great danger so much so that the chains had to be abandoned altogether. Until the year 1862 flat hempen ropes were used exclusively. Then Newell brought his metallic wire ropes to such a state of perfection that they were substituted for the hempen ones. Up to the present day the steel rope is without a rival, and it has done much to make mechanical haulage both possible and general. The rope is usually driven by an engine at the surface, but sometimes the engine is placed underground and run by steam or compressed air. The speed of hoisting or winding, as it is termed, compares favorably with that of railway trains.
At many of the large mines the coal is lifted a depth of half a mile in less than a minute. Owing to greatly improved appliances in shaft machinery accidents are very rare. In the best regulated coal mines there are automatic appliances, in case of the cage becoming liberated from the rope, to prevent its falling down the shaft again.
The greatest danger to which the coal miner's life is, and always has been, exposed is that which awaits him in the form of explosions of inflammable gases. In the early years of the Century these explosions received the attention of all the leading scientists. Until the introduction of Sir Humphrey Davy's safety lamp in 1816, coal mines were tested, before the men entered them by "trying the candle;" the presence of the deadly fire-damp being shown by the flame assuming a bluish color, and other gases by various peculiarities in the tint and shape of the flame. Complicated improvements which have since been made on the Davy lamp, together with the introduction of electric light wherever available, have in recent years combined to reduce this danger to a minimum.
Next to coal, iron has been the greatest factor in the phenomenal industrial progress attained by the genius and wisdom of the Nineteenth Century. The history of iron and the manufacture and use of steel are as old as civilization itself. The Chinese were familiar with steel fully 2600 B.C., ancient Chinese writings containing descriptions of the processes used in its conversion. The Phoenicians were also acquainted with the use of extremely hardened iron (properly speaking, steel) as their numerous and beautiful works in ornamental metallurgy, and the cutting and engraving of precious stones, for which they were conspicuous among the nations of antiquity, necessarily involved. During the Middle Ages the strength and durability of iron led to its extensive manufacture and use for defensive purposes, and the iron-monger and blacksmith occupied prominent positions among the craftsmen of that darkened period of the world's history.
Crude cast or "Pig" iron is the most widely used metal of modern times and the most indispensable in the industrial arts, either as the material out of which articles may be formed by the operation of casting, or as the substance from which the purer forms of the metal may be obtained.
The history of the metallurgy of iron and steel during the present Century is marked by four epoch-making inventions, beside which all others sink into comparative obscurity. These four inventions, which completely revolutionized the industry to which they were applied, are: The hot blast for blast furnaces, invented by James Neilson in 1828, which doubled the output of the blast furnace without any extra fuel; the Bessemer process for the conversion of steel, invented in 1856; the Siemens regenerating furnace in 1862; and the Gilchrist-Thomas or basic process of making steel from iron containing phosphorus, invented in 1880. In following the development of the iron industry it is well to remember that the blast furnace producing cast iron has two offices to perform. It has to reduce the ore to a state of metal, which process is effected in the central and upper part of the furnace by the action of carbon and carbonic monoxide. The reduced metal is then melted, and in this operation it absorbs carbon and becomes cast iron, while the foreign matters of the ore fuse with the coke-ash and are withdrawn in the form of slag.
The very early iron furnaces did not produce cast iron, unless by accident; they produced a steely wrought iron that did not melt, but had to be picked out of the furnace. This was due to the fact that the furnaces, being very small, used charcoal as fuel, which had great power of reduction, but would not make sufficient heat to melt the iron. In 1828 Neilson conceived the idea of feeding all kinds of furnaces with blasts of hot air. The invention proved a great success and effected a great saving in fuel, with a phenomenal increase in the production of the English furnaces. No further notable improvements were made until 1845, when Budd conceived the idea of utilizing the gas which escaped from the mouth of the furnace by drawing it below and heating the air for the hot blast with it. Soon after this the closed top to the furnace was invented.
With the exception of some special processes, entailing endless toil and great expense, the majority of steel in early days was converted from cast iron by the puddling process. This consisted in melting the cast iron in the form of pigs on the hearth of a reverbatory furnace, in contact with iron cinder and iron ore, accompanied by a constant stirring of the melted metal, or "puddling" as it is termed. After being worked into shape by hammers and rolls it was enclosed in cases of horn shavings and heated to a high temperature for many hours. When re-moved from the casing the metal showed a blistered surface, and was called blister steel. Puddling in this fashion necessarily involved a great amount of hard manual labor, and various attempts were made to get rid of it. Many minor inventions were made for the production of steel before the great revolutionary one of Sir Henry Bessemer put in its appearance in 1856. This is regarded one of the greatest inventions the world has ever seen, and has done more than almost anything else to revolutionize industry. Bessemer began his experiments in the production of steel from pig iron by use of the air blast. Cast iron was melted in a reverbatory furnace, from which it ran into these four great epoch-making inventions would necessitate the writing of a volume devoted exclusively to the history of the iron and steel industry.
The discovery of aluminum, the lightest metal known, is probably the most novel and notable attainment of Nineteenth Century metallurgy. The alchemists of the Middle Ages speculated on the composition of alum and decided that it must have an earthy base. About 1600 Stahl said this base was similar to lime. In 1724, Fr. Hoffman first announced the correct idea that the base of alum is a substance distinct from all earthy bases. This was demonstrated by Marggraf in 1754, and in 1760 Professor Baron, of Paris, announced that he had tried without success to reduce it to metal. Yet the belief that it would ere long be isolated was so strong that in 1762 this earthy base was named alumine. The discoveries by Lavoisier and Priestly, about 1780, led directly to the idea that alumina is the oxide of a metal that had not been isolated, and during the next forty years all imaginable methods of reducing it were tried without success. In 1824, a Swede named Oersted, discovered a method of making from alumina a combination of aluminum with chlorine, the first being an element of clay and the latter of common salt.
In 1827 Frederick Wohler, a German professor, found that metallic potassium had such a strong affinity for chlorine that it would take it from the aluminum chloride and leave the metal free. The aluminum obtained by Wohler was, however, only as a fine powder, which resisted all efforts to make it amalgamate. The trouble was to find an element with such a strong affinity for oxygen that it would take it away from the aluminum, leaving the latter free. In 1854 Ste. Clair Deville experimented with potassium with the much-desired result, but the product when obtained cost more than its weight in gold, the actual cost of a pound of the metal being about $200. Then Deville tried the mixing of aluminum chloride with common salt, subjecting the liquid to the decomposing force of a strong electric current, The product so obtained cost but little less than the first. Then he tried metallic sodium instead of potassium, by which process he was able to manufacture aluminum at a cost of $8 per pound. No cheaper method was discovered until 1886. In that year a new process for making sodium reduced the cost of that chemical from $1 per pound to less than 25 cents. This had the effect of materially reducing the price of aluminum production, and by 1888 the metal was selling for $5 per pound, the total output being one ton weekly. But the sodium process was soon to be a thing of the past, for in 1889 Charles M. Hall, of Oberlin, Ohio, patented an electrolytic process, and started a small plant for the manufacture of aluminum on the bank of the Allegheny River, about eighteen miles above Pittsburg. The process consisted of a bath of aluminum fluoride and sodium fluoride, in which alumina has been dissolved. This mixture is kept melted by the heat of a strong electric current, which decomposes the alumina in the solution without decomposing the bath in which it is dissolved. By this process the metal is now being made at a cost less than 50 cents per pound, and numerous factories for its manufacture and that of its alloys have been established both in this country and abroad.
The possibilities of aluminum are infinite. It is about as light as oak wood, being about one-fourth as light as iron and has greater resistance than the very best steel. It stands high in the list of malleable metals and can be drawn into a wire 1-250th of an inch in thickness. It is an excellent conductor of electricity, and would at 20 cents per pound take the place of copper for all electrical purposes.
In shipbuilding, where lightness is demanded, aluminum meets every requirement. France and Germany have several aluminum torpedo-boats, and pleasure yachts are being built every year of this metal. In Germany two army corps are equipped with aluminum, the equipment including every article of metal carried on the person. Paris has several aluminum cabs, and aluminum horse-shoes and aluminum sulkies are made for some of the great racers. The Twentieth Century will no doubt see it sup-plant iron and steel to a great extent, as the time is certain to come when it can be manufactured as cheaply as those products. It is well known that aluminum is present in every clay bank, and it would be difficult to say more plainly how common it is. The only question is how to separate it from the clay at a cost that will put it within reach of the mechanic and the manufacturer, and as it is believed that discovery is not far off, the predicted "Aluminum Age" may be near at hand.
There is so much of the romantic and picturesque in the history of the past fifty years' developments in the mining of the precious metals and gems, that the recounting of it would seem to be more within the province of the novelist than of the sober chronicler of ordinary events. In that short period the two richest gold fields of modern times have been discovered, and diamonds and other precious stones have been found in such profusion as to cause a depreciation of at least one-third in the value of some of them, as, for instance, diamonds.
Probably the most contagious gold fever that ever spread over an adventure-loving world was that which broke out in May, 1848, when Sam Brannan, the leader of the Mormons in California, pranced through the streets of San Francisco, swinging his hat and brandishing a bottle of gold and shouting at the top of his voice, "Gold, Gold, Gold from the American River." On the 19th of January of that year James Wilson Marshall, a carpenter, while at work on the tail race of Sutter's Mill, in Eldorado County, had made the discovery of the precious yellow metal. The outcry of Sam Brannan was as the touching of flame to tow. The whole town became ablaze with excitement. Everybody left his shop, store, or office and made a mad rush for Sutter's Mill, where the Mormon told them they would find the very river beds filled with golden gravel. The cry of Sam Brannan went all over the world, and. the wonderful tale of an El Dorado was transported North, East, South, and West. It reached Hawaii first, and twenty-seven vessels, loaded with whites and natives, set sail before October 1. Two-thirds of the population of Oregon deserted hearth and home and sought the gold fields. From six cities, New York, Boston, Salem, Philadelphia, and Baltimore, sixty-one vessels, averaging fifty passengers each, set sail for California between the middle of December and the middle of January, ' 1849. Sixty vessels cleared for the same voyage around Cape Horn from New York alone. During the winter and spring 250 vessels sailed from Eastern ports. The long five months' trip around Cape Horn was a wearisome outlook to the feverish gold seekers. There was a mad scramble for passage on any kind of craft that would float. The California, a side-wheel steamer of 1,050 tons, was the first of these ships to pass through the Straits of Magellan. At the South American ports competition was so fierce that steerage tickets were eagerly snatched up at $1,000 each. When the ship arrived at San Francisco and the passengers had swarmed off into the jubilating town, every one of the officers and crew ran away except the captain and the assistant engineer. It was impossible to man the vessel for the return trip and she drifted helplessly about in the bay for a long time. Before the middle of January, 1849, there was not an important shipping port in the world that did not contain at least two or three vessels that were fitting out for the Golden Gate. Even the farthest East was not beyond the stretch of the contagion. China began to throw a stream across the Pacific, and Australia placarded the streets of her chief cities with glowing signs : "Gold, gold, gold, gold in California." In the early part of the year 316 vessels from foreign ports sailed through the Golden Gate. Most of these vessels were deserted by their crews as soon as they touched the land. At one time more than 500 ships were counted in the bay, and not one could boast a crew or guard. On a par with this great migration by water was the grand overland movement that began in the spring of 1849, as soon as passage over the plains and mountains was feasible. The story of the overland route is one long tragedy. The rallying points of this migration were St. Joseph, Mo., and Independence, Mo., on the Missouri River, from which stretched the two long weary trails. Thousands and thou-sands of vehicles of every description rolled into these headquarters early in April. In May the great caravans set out, and before June ro, 5,095 wagons had passed a certain point on the Humboldt River trail, and it was reckoned that a thousand more were left behind on account of sickness and death, or, as often happened, massacres by the Indians. The rear ranks of the long processions of that year were overtaken by a terrible scourge of cholera, and 5,000 died on the march, while other thou-sands were prevented from continuing the trail.
Considering the crude processes then in vogue for the mining of gold, the yield that rewarded the brave argonauts was truly phenomenal. In the first year $10,000,000 worth was taken out; this increased to $40,000,000 in 1849; $50,000,000 in 1850; $55,000,000 in 1851; $60,-000,000 in 1852 ; and it reached its highest point in 1853, when a total value of $65,000,000 was recovered. During these first six years the methods of extracting the gold were very crude, and therefore very wasteful. The mining was carried on in what was termed placer deposits, and the favorite tools of the forty-niner were the pan, the rocker, the Long Tom, and the sluice box. The rich alluvial deposits becoming worked out in the course of time, the miner turned his attention to the gold-bearing rock. Then the mining of gold became a more difficult and costly matter. Science, skill, and capital were demanded, and chemistry was called in to determine the composition of the various ores. The pan, the rocker, and the Long Tom gave place to the highly organized machinery of the stamp mill, with its costly stamp batteries, amalgamating pans, and concentrating tables. In due time the rebellious ores were treated by roasting, and the various leaching processes were introduced, by which practically the last trace of gold could be recovered from the tailings. There were also perfected a number of systems of hydraulic mining, whereby enormous deposits of gold-bearing gravel can be worked to advantage. As its name indicates, the mining is done by the action of water, which is discharged under enormous pressure against the gravel bank or bowlder, thoroughly seggregating it and washing it into sluices, where the gold is deposited.
During the first flush of the gold excitement there was little or no attention paid to the mining of the less valuable metal silver, although it abounded in close proximity to the gold diggings. To the two and a half million ounces of gold taken out in 1850, there were only 38,000 ounces of silver. This rose to 12,375,360 ounces in 1870, and reached the maximum in 1890, when it amounted to 54,517,440.
Since the discovery of gold in California, rich deposits have been located and worked in all the Rocky Mountain states and in the Black Hills of Dakota, but, with the exception of the Cripple Creek Colorado excitement of 1895-1896, nothing approaching the frenzy of '49 occurred until the news was spread that treasure of untold value had been found in Alaska. Then the scenes of the early fifties were enacted all over again. The excitement reached its height in 1898, and men, and women, too, flocked from the utter-most parts of the earth to the frozen and barren regions of the Yukon and the Klondike. The tragedies of the over-land, or "backdoor route," as it is called in this case, were repeated. Bleached bones strewed the way over the Canadian Rockies and through the mountains of Eastern Alaska for thousands of miles, and the name of Chilkoot Pass became synonymous with that of death. During the winter of 1897-98 and the following summer every available vessel in the Pacific ports was put into requisition, and hundreds of thousands made the long sea journey to St. Michels, thence up the Yukon, sixteen hundred miles to Dawson City, the metropolis of the New El Dorado. Owing to climatic restraints, it has been impossible to determine the richness of the new treasure land, or to even make a conjecture regarding its possibilities.
There is not space here to even briefly describe the wonderful and costly mechanisms that have been introduced into the gold-mining industry in very recent years. The principal innovations, however, are the steam dredge, used for scraping up the gravel from rivers, and the peripatetic mining machine on wheels; built by the Pullman Company for the smelting and testing of ores.
The development of copper mining industry has been no less remarkable than that of gold. The discovery of the famous Cliff copper mine on the shores of Lake Michigan in 1844 opened up one of the richest deposits of this mineral that has ever been known. The first recorded production was one of 12 tons, taken from this mine in 1845, which increased to 150 tons in 1848. Within the last twenty years the increase of production has been with-out a parallel. From 27,000 tons in 1880 it had attained to more than 200,000 tons in 1897, an amount which is greater than the total production of all the other countries of the world combined. Although copper is worth to-day only one-half what it was twenty-five years ago, the out-put is more than thirteen times as great. This success has been achieved entirely by the introduction of improved machinery for the mining of the raw material and in efficient processes of metallurgy in the division and refining of the ore. The great Calumet and Hecla mines in Michigan each treat not less than 1,000 tons, and often as much as 3,000 tons of rock daily. The machinery used in handling this material is the most powerful of its kind compressors and rock drills, pumps for lifting water from the mines ; huge engines for hoisting the rocks, and enormous steam stamp mills where the ore is prepared for the hydraulic processes of concentration which separate it from the copper. An immense quality of water is required by these mills not less than thirty tons for each ton of rock treated and in the pumping of the water from the lake some of the largest pumping engines in the world are used.
The mining and metallurgy of the baser metals zinc, lead, and tin, and the manufacture of tin plate, have in recent years become pre-eminently American industries. The extraordinarily large deposits of zinc and lead which have been found in Kansas and Missouri have led to some notable improvements in the methods of smelting, one of the most notable being the adoption of the electro-magnet. A new process for the manufacture of paint is one of the important outgrowths of the Kansas lead industry. The old process of manufacturing white lead by the slow corrosion of pig lead has been done away with entirely. The intent of the new process is to turn the ore directly into white lead, and to manufacture that into paint. This process started with the idea of saving white lead from the smoke and fumes of the smelter. It has reached such economical development that the ability of the workmen to stand before the furnace is the measure of the amount of lead which shall pass into the more valuable product. The heat to make the new process effective must be of the most intense character, the furnace being fed with broken car wheels or anything that will produce sufficient heat to turn the lead into smoke and fumes from which the white lead is extracted.
There have been no industrial phenomena so distinctly characteristic of the Nineteenth Century as the sudden discovery and development of the utilities of the oil and natural gas fields of Pennsylvania, West Virginia, and Ohio. The rapidity with which advantage has been taken of the newly discovered resources, and the manner with which they have been applied to the widest variety of manufacturing purposes, have resulted in important modifications in a number of industries. Although petroleum had been known from the earliest times, the history of the industry really dates from August 28, 1859, when oil was struck at a depth of 69 1/2 feet along the banks of Oil Creek, Venango County, Pa. This well flowed a thousand gallons a day and the excitement that followed the discovery rivaled the gold stampede of ten years before. Before the close of the year 1860, 2,000 flowing wells had been sunk, and the daily output of seventy-four of them was 1,165 barrels of 40 gallons each. Oil Creek below Titusville, the valley of the Allegheny from Franklin to Warren County, and the banks of French Creek, became one bustling city of derricks. Poor, hardworking farmers were made multi-millionaires in the course of a night. Small villages reared themselves into veritable metropolises, and a period of recklessness and wild extravagance ensued, which has never been equaled in the history of any mining camp. Although the abnormal features of the early development of this particular territory have since disappeared, it is still considered one of the richest oil-producing localities in the world. More recent but equally fruitful discoveries of oil and natural gas have been made in West Virginia and Ohio and a small district near Pittsburg, Pennsylvania, while the fields of Siberia have been opened to the world.
The development of natural gas, always to be found in greater or less quantities in petroleum territory, dates back to 1878, but it did not come into general use for domestic and manufacturing purposes until 1884. It was then piped to Pittsburg and for a few years the Smoky City lost its right to that time-honored pseudonym. In 1887 extensive gas fields were discovered in Indiana, but now, after a dozen years, they, t00, have become partially exhausted, although the economy of to-day may in part atone for the extravagance of the past and make them available for a generation to come. The towns and cities that have sprung up around the natural gas centers show evidence that they may hold and increase their prosperity, even should the supply of gas become exhausted.
For many years it was thought impracticable for America to even attempt the manufacture of tin plate, and that industry, which has now reached considerable proportions, really dates its birth to the passage 0f the tariff act of 1890. Since then American tin plate competes success-fully with the very best Cornwall product, and in view of the fact that the Black Hills of Dakota contain 500 square miles of tin-producing district, containing more tin than all the other tin mines of the world put together, the future possibilities of the industry are unlimited. Improved methods employed in the treatment of the plates are all the results of the past forty years. With the exception of a few of the Cornwall factories, hand-made tin plate is a thing of the past. Briefly described, the present process consists, first, in placing the iron or steel sheet to be coated, in a solution of sulphuric acid or "black pickle" for the removal of the scale. Washed of the "black pickle" they are then annealed in cast-iron boxes filled with sand to exclude the air. After ten or twelve hours' roasting, the plates are passed through cold rolls and annealed a second time, when they are ready for the second, or "white pickle." After this they are dipped in the tinning pot, where they receive the necessary coating.
As has already been mentioned, the value of diamonds has in recent years depreciated fully one-third. This is due partly to improved methods of cutting and partly to the discovery of enormous quantities of the gem in South Africa in 1869 and 1870. In the beginning of the present Century diamonds were extremely scarce, because of the primitive way of working the mines, there being no machinery for the purpose of excavation. The South African diamonds were at first found in gravel surface and entailed scarcely any expense in mining. At that time the seat of the diamond-cutting industry was at Amster-dam, and the number of establishments did not exceed eight. The development of the African mines so increased the trade, however, that at present there are between fifty and sixty large diamond-cutting houses in Amsterdam alone. Antwerp in 1870 had four establishments and 200 diamond workers ; now it has eighty establishments and 4,000 workers. Large diamond-cutting establishments have also been founded in London, Paris, Geneva, and Berlin, with smaller ones in several of the minor cities of France and Germany, and it is estimated that there are now 16,500 persons engaged in the diamond industry in Europe.
Although the discoveries of precious stones in America have thus far not been such as to warrant high expectations, nevertheless gems of exceeding value have been found in various states. Sapphires of extreme beauty and great intrinsic value have been mined in Idaho; New Mexico has in late years produced some magnificent turquoises, together with opals, emeralds, and garnets. Diamonds are met with in well defined districts of California, North Carolina, Georgia, and Wisconsin. Exquisite beryls have been found in Colorado, Connecticut, Virginia, and North Carolina.
With the marvelous facilities for quarrying and shipping, the production of building stones has become one of the most thoroughly organized industries peculiar to the present Century. The value of granite produced annually in the United States approximates $10,000,000; of marble, $2,800,000; of slate, $3,000,000; of sandstone, $4,000,000; of limestone, $15,000,000, and of bluestone, $750,000.