Well-informed persons are aware of the part which machinery in general has had on modern industrial life. But the profound influence which machine tools have had in that development is scarcely realized, even by tool builders themselves.

Three elements came into industrial life during the latter part of the eighteenth century. First, the development of modern banking and the stock company brought out the small private hoards from their hiding places, united them, and made them available for industrial undertakings operating on the scale called for by modern requirements. Second, Watt’s development of the steam engine and its application to the production of continuous rotative motion gave the requisite source of power. But neither the steam engine itself nor the machinery of production was possible until the third element, modern machine tools, supplied the means of working metals accurately and economically.

It is well to glance for a moment at the problems which were involved in building the first steam engine. Watt had been working for several years on the steam engine when the idea of the separate condenser came to him on that famous Sunday afternoon walk on the Glasgow Green, in the spring of 1765, and, to use his own words, “in the course of one or two days the invention was thus far (that is, as a pumping engine) complete in my mind.”[1] He was a skilled instrument maker and his first small model was fairly successful, but when he undertook “the practice of mechanics in great,” his skill and all the skill of those about him was incapable of boring satisfactorily a cylinder 6 inches in diameter and 2 feet long; and he had finally to resort to one which was hammered. For ten weary years he struggled to realize his plans in a full-sized engine, unable to find either the workmen or the tools which could make it a commercial success. His chief difficulty lay in keeping the piston tight. He “wrapped it around with cork, oiled rags, tow, old hats, paper, and other things, but still there were open spaces left, sufficient to let the air in and the steam out.”[2] Small wonder! for we find him complaining that in an 18-inch diameter cylinder, “at the worst place the long diameter exceeded the short by three-eighths of an inch.” When Smeaton first saw the engine he reported to the Society of Engineers that “neither the tools nor the workmen existed that could manufacture so complex a machine with sufficient precision.”[3]

Smeaton himself had designed a boring machine in 1769 for the Carron Iron Works for machining cannon, an illustration of which is given in Fig. 1.[4] It consisted of a head with inserted cutters mounted on a long, light, overhung boring bar. The work was forced forward on a rude carriage, as shown. The method of supporting the cutter head, indicated in the section, shows an ingenious attempt to obtain a movable support from an inaccurate surface. One need hardly say that the work resulting was inaccurate.

Fortunately, in 1774, John Wilkinson, of Bersham, hit upon the idea, which had escaped both Smeaton and Watt, of making the boring bar heavier, running it clear through the cylinder and giving it a fixed support at the outboard end as shown in Fig. 7. The superiority of this arrangement was at once manifest, and in 1776 Boulton wrote that “Mr. Wilkinson has bored us several cylinders almost without error; that of 50 inches diameter, which we have put up at Tipton, does not err the thickness of an old shilling in any part.”[5] For a number of years, Wilkinson cast and bored all the cylinders for Boulton & Watt.

The importance to Boulton & Watt of the timely aid of Wilkinson’s boring machine can hardly be overestimated. It made the steam engine a commercial success, and was probably the first metal-working tool capable of doing large, heavy work with anything like present-day accuracy.[6]

We hardly realize the crudity of the tools available in the eighteenth century. In all machinery the principal members were of wood, as that could be worked by the hand tools then in use. The fastenings and smaller parts only were of metal, and consisted of castings and forgings fitted by hand. There were some lathes of the very simplest type. Most of them were “pole” lathes, operated by a cord reaching from a foot treadle, around the work itself, and up to a pole or wooden spring attached to the ceiling. The work rotated alternately forward and backward, and was caught with a hand tool each time as it came forward. Two are shown in Fig. 2, one at the back and one at the left. Only the very best forms had continuous motion from a direct drive on the live spindle, as shown at the right of the same figure. This figure is reproduced from the French Dictionnaire des Sciences, published in 1772. Such lathes were almost useless for metal cutting, as they lacked both the necessary power and a holding device strong enough and accurate enough to guide a tool. The slide-rest, while it had been invented, had not been put into practical form or come into general use. There were a few rude drilling and boring machines, but no planing machines, either for metal or wood. The tool equipment of the machinist, or “millwright,” as he was called, consisted chiefly of a hammer, chisel and file. The only measuring devices were calipers and a wooden rule, with occasional reference perhaps to “the thickness of an old shilling,” as above. Hand forging was probably as good as or better than that of today. Foundry work had come up to at least the needs of the time. But the appliances for cutting metal were little better than those of the Middle Ages.

Such was the mechanical equipment in 1775; practically what it had been for generations. By 1850 it was substantially that of today. In fact, most of this change came in one generation, from about 1800 to 1840. Since that time there have been many improvements and refinements, but the general principles remain little changed. With so wonderful a transformation in so short a time, several questions arise almost inevitably: Where did this development take place, who brought it about, and why was it so rapid?

The first question is fairly simple. England and America produced the modern machine tool. In the period mentioned, England developed most of the general machine tools of the present day; the boring machine, engine lathe, planer, shaper, the steam hammer and standard taps and dies. Somewhat later, but partially coincident with this, America developed the special machine tool, the drop hammer, automatic lathes, the widespread commercial use of limit gauges, and the interchangeable system of manufacture.

In a generalization such as this, the broad lines of influence must be given the chief consideration. Some of the most valuable general tools, such as the universal miller and the grinder, and parts of the standard tools, as the apron in the lathe, are of American origin. But, with all allowances, most of the general machine tools were developed in England and spread from there throughout the world either by utilization of their design or by actual sale. On the other hand, the interchangeable system of manufacture, in a well-developed form, was in operation in England in the manufacture of ships’ blocks at Portsmouth shortly after 1800; and yet this block-making machinery had been running for two generations with little or no influence on the general manufacturing of the country, when England, in 1855, imported from America the Enfield gun machinery and adopted what they themselves styled the “American” interchangeable system of gun making.[7]

The second question as to who brought this change about is not so simple. It is not easy to assign the credit of an invention. Mere priority of suggestion or even of experiment seems hardly sufficient. Nearly every great improvement has been invented independently by a number of men, sometimes almost simultaneously, but often in widely separated times and places. Of these, the man who made it a success is usually found to have united to the element of invention a superior mechanical skill. He is the one who first embodied the invention in such proportions and mechanical design as to make it commercially available, and from him its permanent influence spreads. The chief credit is due to him because he impressed it on the world. Some examples may illustrate this point.

Leonardo da Vinci in the fifteenth century anticipated many of the modern tools.[8] His sketches are fascinating and show a wonderful and fertile ingenuity, but, while we wonder, we smile at their proportions. Had not a later generation of mechanics arisen to re-invent and re-design these tools, mechanical engineering would still be as unknown as when he died.

Take the slide-rest. It is clearly shown in the French encyclopedia of 1772, see Fig. 3, and even in an edition of 1717. Bramah, Bentham and Brunel, in England, and Sylvanus Brown,[9] in America, are all said to have invented it. David Wilkinson, of Pawtucket, R. I., was granted a patent for it in 1798.[10] But the invention has been, and will always be, credited to Henry Maudslay, of London. It is right that it should be, for he first designed and built it properly, developed its possibilities, and made it generally useful. The modern slide-rest is a lineal descendant from his.

Blanchard was by no means the first to turn irregular forms on a lathe. The old French rose engine lathe, shown in Fig. 4, embodied the idea, but Blanchard accomplished it in a way more mechanical, of a far wider range of usefulness, and his machine is in general use to this day.

To the third question as to why this development when once begun should have been so rapid, there are probably two answers. First, an entirely new demand for accurate tools arose during these years, springing from the inventions of Arkwright, Whitney, Watt, Fulton, Stephenson and others. The textile industries, the steam engine, railways, and the scores of industries they called into being, all called for better and stronger means of production. While the rapidity of the development was due partly to the pressure of this demand, a second element, that of cumulative experience, was present, and can be clearly traced. Wilkinson was somewhat of an exception, as he was primarily an iron master and not a tool builder, so his relationship to other tool builders is not so direct or clear. But the connection between Bramah, Maudslay, Clement, Whitworth and Nasmyth, is shown in the “genealogical” table in Fig. 5.

Bramah had a shop in London where, for many years, he manufactured locks and built hydraulic machinery and woodworking tools. Maudslay, probably the finest mechanician of his day, went to work for Bramah when only eighteen years old and became his foreman in less than a year. He left after a few years and started in for himself, later taking Field into partnership, and Maudslay & Field’s became one of the most famous shops in the world.

Sir Samuel Bentham, who was inspector general of the British navy, began the design of a set of machines for manufacturing pulley blocks at the Portsmouth navy yard. He soon met Marc Isambard Brunel, a brilliant young Royalist officer, who had been driven out of France during the Revolution, and had started working on block machinery through a conversation held at Alexander Hamilton’s dinner table while in America a few years before. Bentham saw the superiority of Brunel’s plans, substituted them for his own, and commissioned him to go ahead.

In his search for someone to build the machinery, Brunel was referred to Maudslay, then just starting in for himself. Maudslay built the machines, forty-four in all, and they were a brilliant success. There has been considerable controversy as to whether Bentham or Brunel designed them. While Maudslay’s skill appears in the practical details, the general scheme was undoubtedly Brunel’s. In a few of the machines Bentham’s designs seem to have been used, but he was able enough and generous enough to set aside most of his own designs for the better ones of Brunel.

Of the earlier tool builders, Maudslay was the greatest. He, more than any other, developed the slide-rest and he laid the basis for the lathe, planer and slotter. His powerful personality is brought out in Nasmyth’s autobiography written many years later. Nasmyth was a young boy, eager, with rare mechanical skill and one ambition, to go to London and work for the great Mr. Maudslay. He tells of their meeting, of the interest aroused in the older man, and of his being taken into Maudslay’s personal office to work beside him. It is a pleasing picture, the young man and the older one, two of the best mechanics in all England, working side by side, equally proud of each other.

Joseph Clement came to London and worked for Bramah as chief draftsman and as superintendent of his works. After Bramah’s death he went to Maudslay’s and later went into business for himself. He was an exquisite draftsman, a fertile inventor, and had a very important part in the development of the screw-cutting lathe and planer. Joseph Whitworth, the most influential tool builder of the nineteenth century, worked for Maudslay and for Clement and took up their work at the point where they left off. Under his influence machine tools were given a strength and precision which they had never had before. Richard Roberts was another pupil of Maudslay’s whose influence, though important, was not so great as that of the others.

We have an excellent example of what this succession meant. Nasmyth tells of the beautiful set of taps and dies which Maudslay made for his own use, and that he standardized the screw-thread practice of his own shop. Clement carried this further. He established a definite number of threads per inch for each size, extended the standardization of threads, and began the regular manufacture of dies and taps. He fluted the taps by means of milling cutters and made them with small shanks, so that they might drop through the tapped hole. Whitworth, taking up Clement’s work, standardized the screw threads for all England and brought order out of chaos.

Some account of the growth of machine tools in the hands of these men will be given later. Enough has been said here to show the cumulative effect of their experience, and its part in the industrial advance of the first half of the nineteenth century. Similar successions of American mechanics will be shown later.

Writing from the standpoint of fifty years ago, Smiles quotes Sir William Fairbairn: “‘The mechanical operations of the present day could not have been accomplished at any cost thirty years ago; and what was then considered impossible is now performed with an exactitude that never fails to accomplish the end in view.’ For this we are mainly indebted to the almost creative power of modern machine tools, and the facilities which they present for the production and reproduction of other machines.”[11]