330. Advantages of machines.—Practically, however, the great extension in the use of machinery has depended on the power obtained from coal through steam. Only in the period since the adoption of improved forms of steam-engine have we realized the possibilities of machines. They can be applied only to certain classes of work, especially that involving the constant repetition of an operation which can be easily regulated either by the machine itself or by a laborer supervising it. We can use machines, for instance, to make cloth and even to make clothes, but we do not use them in the operations of dressing and undressing. In their proper field, however, they are indispensable. They will accomplish tasks which are too great or too small for human hands. They repeat a process or copy a model with absolute fidelity. They never grow tired and they have no human failings; they often economize time and materials. Finally, and this is the point of decisive importance, in many lines of work they, furnish the product at a cost far below that of hand labor.

331. Revolution in old industries effected by machinery.—To describe the manifold applications of machinery in the nineteenth century, within the limits of this manual, is impossible. Let the reader glance from the book to the objects surrounding him, and make a list of the ten objects which first attract his attention. If he will trace their history he will find, in all probability, that they are all the products of complicated machinery, which has been developed from the simplest beginnings in the course of the century. He will probably experience difficulty in finding a familiar object which has not been subjected to machine processes unknown in 1800. Machinery has heightened human productivity in certain lines a hundred or even a thousand fold. At the Atlanta Cotton Exposition of 1881, two carders, two spinners, and one weaver, from the mountain region of Georgia, could produce eight yards of coarse cotton cloth in a day of ten hours. The same number of persons in a modern cotton factory could produce 800 yards by machinery. The cotton goods produced for home consumption in the United States by 160,000 laborers at that time, would have required the services of 16,000,000 laborers without machinery. Again, a skilful woman can knit 80 stitches a minute by hand; a machine enables her to make 480,000.

332. Introduction of new industries.—Machinery has not only revolutionized old industries; it has created many new ones. A distinguished American economist expressed the opinion, about 1890, that half of all those who were then earning their living by industrial pursuits did so in occupations that not only had no existence, but which had not even been conceived of, a hundred years before. I may write with a steel pen, with a fountain pen, or with a typewriter; whichever choice I make I am giving employment to a group of mechanical laborers who did not exist in 1800. Taking a particular city as an example, the industrial specialities of Leipzig are said to have increased from 118 in 1751 to 557 in 1890, a growth of 372 per cent. Nor must we limit our view of the effects of machinery to the mechanical pursuits which are carried on about us. Increased efficiency due to the use of machinery has set men free from other pursuits to engage in commerce, education, domestic service, etc.

333. Importance of iron in the age of machinery.—One particular industry deserves special consideration here, by reason of the quality of its product rather than of the quantity of laborers employed or the mere exchange value of the output. Without iron the modern age of machinery would be, at best, of stunted growth. Jevons characterized admirably the modern industrial system when he said that steam is its motive power and iron is the fulcrum and the lever. It is safe, I think, to challenge the ordinary reader of the present day to name a machine which is not composed largely or almost wholly of iron. The whole structure of our modern industry depends on the means of getting cheap iron. “Without it the engine, the spinning-jenny, the power-loom, the gas- and water-pipe, the iron vessel, the bridge, the railway—in fact, each one of our most important works—would be impracticable from the want and cost of material.”

334. Scarcity of iron before the nineteenth century.—Returning to the period about 1800 we find ourselves in a different world. I have described in a previous chapter the improvements effected in the manufacture of iron in the eighteenth century. Great as was the promise of these improvements, it waited long for full realization; well into the nineteenth century iron remained relatively scarce and dear and was spared in every possible way. A youth destined to play a leading part in the iron age (Joseph Nasmyth) visited the Carron Iron Works in 1823, and here is the description which he gives of a celebrated foundry and machine shop, associated with the construction of the first working steam-engine by Watt. “Much of the machinery continued to be of wood. Although effective in a general way it was monstrously cumbrous. It gave the idea of vast power and capability of resistance, while it was far from being so in reality.” If this was the condition at the Carron Iron Works, what must it have been in ordinary factories?

335. Development of machine tools for working iron.—Iron was little used, partly because it was hard to get and partly because it was hard to work. There were in England about 1800 only three good machine shops, where small steam-engines were built. The equipment of even the best machine shop would seem now wretchedly inadequate, and Stephenson was greatly hampered, in building his first locomotive, by the lack of good machine tools, for working metals. William Fairbairn said in his presidential address before the British Association at Manchester, “When I first entered this city [about 1813] the whole of the machinery was executed by hand. There were neither planing, slotting, nor shaping machines; and, with the exception of very imperfect lathes, and a few drills, the preparatory operations of construction were effected entirely by the hands of the workmen.” About 1825 to 1830, however, with the growth in demand for iron-working apparatus, there began a rapid development of this branch of manufacture, one step in advance leading rapidly to another. We may trace the process in the description that Nasmyth gives us of his first machine shop, a shed measuring 24 by 16 feet. “I removed thither my father’s foot-lathe, to which I had previously added an excellent slide-rest of my own making. I also added a ‘slow motion,’ which enabled me to turn cast-iron and cast-steel portions of my great Mandsley lathe. I soon had the latter complete and in action. Its first child was a planing machine capable of executing surfaces in the most perfect style; it was 3 feet long by 1 foot 8 inches wide. Armed with these two most important and generally useful tools, and by some special additions, such as boring machines and drilling machines, I soon had a progeny of legitimate descendants crowded about my little workshop, so that I often did not know which way to turn.” Nasmyth himself made one specially important contribution to iron-working machinery, by the invention of the steam hammer in 1839; the old “bit by bit” system of welding became henceforth unnecessary.

336. Steel, character and utility.—While the limits of our space will not permit us to trace further the development of machine tools, which have been made marvelously efficient in recent years, and while we must also forego a study of the details of iron production, the topic of steel manufacture certainly deserves some consideration. Ordinary cast iron, while strong and hard enough for many purposes, still is brittle by reason of the large proportion of carbon and other impurities which it contains. These impurities may be burned out in the puddling process, and the nearly pure iron thus obtained, called malleable or wrought iron, has a toughness enabling it to resist far greater strains than cast iron can stand. Intermediate between the two irons, and containing one per cent of carbon, more or less, is still another product, steel, which may be made even more tenacious than wrought iron, or even harder than cast iron. Its peculiar property of “taking a temper” is probably known to most readers. The valuable properties of steel have been known and prized for ages, but till well into the nineteenth century it could be used only sparingly; it was commonly manufactured by first making wrought iron, by the tedious process of puddling, and then heating the iron bars in contact with charcoal until they had absorbed the proper amount of carbon. The expense of this process prohibited the use of steel for most purposes; the wrought iron cost $75 a ton and the finished steel $250 or more; and the output would seem to-day inconsiderable.

337. Recent improvements in the manufacture of steel; the Bessemer process.—Many men have contributed to bring the manufacture of steel to its present efficiency, and we may notice only the names associated with the greatest improvements. An Englishman, Bessemer, patented in 1855 the idea, as simple as it is ingenious, of turning cast iron directly into steel by blowing air through it when melted, and so consuming the excess of carbon. It has not proved possible to make good steel according to Bessemer’s original idea, but with a slight modification his process has been wonderfully successful; in present practice all the carbon is burned out by the air current, and then the requisite amount is added before the metal is poured out. Ore containing a large amount of phosphorus is treated by melting it in a converter lined with lime, which removes this dangerous impurity (“basic process”).

338. The open-hearth (Siemens-Martin) process.—Still another contribution to modern methods of steel manufacture, known as the “open-hearth,” or, from the names of its introducers, the Siemens-Martin process, has been of great importance since about 1870. The steel is made from ore or from a combination of different kinds of iron, and, by peculiar devices for economizing the heat of the furnace, the process may be continued so long and regulated so carefully that a product of high quality may be turned out at a moderate cost. The result of all these processes has been to change steel from a luxury to a necessity of modern life. Modern mild steel is 40 per cent stronger than iron, and is tough enough to be tied in a knot or punched in the shape of a bowl when cold. The increase in efficiency due to its substitution for iron in machinery, railroads, ships, and structural work is simply incalculable.

339. Development of the modern chemical industry.—In detailing at such length as I have done the exploits of machinists in the past century, I may tempt the reader to undervalue the contributions of scientists. To guard against that error let us consider briefly the development of the chemical industry, which, like the iron industry, renders a service to modern civilization beyond any measure of dollars and cents. The Frenchman, Lavoisier, had established chemistry on a scientific basis before 1800, but industrial chemistry used still the primitive methods which had been employed for ages. Let us take, for instance, the single substance, carbonate of soda, of prime importance in industrial chemistry, for on it depend the various industries of glass, pottery, soap, photography, paper, etc. This substance was still obtained in the eighteenth century, by burning seaweed and seashore plants and treating their ashes; Spain had a considerable export of barilla, and owed to this product whatever success she attained in the soap manufacture. Leblanc emancipated the soda industry from kelp and barilla, by introducing the process based on sulphuric acid and salt; step by step improvements have been made since then. Sulphuric acid, discarded in the soda industry, has grown in importance notwithstanding; it is the controlling element in the manufacture of other acids, commercial fertilizers, alum, ether, glucose, etc., and in oil refining; and it is produced at a price and of a quality formerly unknown. The discovery of the anilin colors, in 1859, has revolutionized the art of dyeing. The chemist will make you, from coal tar, almost any color or shade desired. He will make you perfumes or flavors; and, if he has failed to construct quinine artificially, he has at least learned, in his attempts, to make substances such as antipyrin and phenacetin, of equal value for other purposes.