find a more decided change or advance over 1764, in all that has been changed or improved since then, than in this very department of applied mechanics. To-day such a model as Watt constructed in the cellar would be simple work indeed. Even the gasoline or the electric motor of to-day, though complicated far beyond the steam model, is now produced by automatic machinery. Skilled workmen do not have to fashion the parts. They only stand looking on at machinery-itself made by automatic tools-performing work of unerring accuracy. Had Watt had at his call only a small part of the inventor's resources of our day, his model steam engine might have been named the Minerva, for Minerva-like, it would have sprung forth complete, the creature of automatic machinery, the workmen meanwhile smilingly looking on at these slaves of the mechanic which had been brought forth and harnessed to do his bidding by the exercise of godlike reason. The model was ready after six months of unceasing labor, but notwithstanding the scrupulous fastidiousness displayed by Watt in the workmanship of all the parts, the machine, alas, "snifted at many openings." Little can our mechanics of to-day estimate what "perfect joints" meant in those days. The entire correctness of the great idea was, however, demonstrated by the trials made. The right principle had been discovered; no doubt of that. Watt's decision was that "it must be followed to an issue." There was no peace for him otherwise. He wrote (April, 1765) to a friend, "My whole thoughts are bent on this machine. I can "think of nothing else." Of course not; he was hot in the chase of the biggest game hunter ever had laid eyes on. He had seen it, and he knew he had the weapons to bring it down. A larger model, free as possible from defects which he felt he could avoid in the next, was promptly determined upon. A larger and better shop was obtained, and here Watt shut himself up with an assistant and erected the second model. Two months sufficed, instead of six required for the first. This one also at first trial leaked in many directions, and the condenser needed alterations. Nevertheless, the engine accomplished much, for it worked readily with ten and one-half pounds pressure per square inch, a decided increase over previous results. It was still the cylinder and its piston that gave Watt the chief trouble. No wonder the cylinder leaked. It had to be hammered into something like true lines, for at that day so backward was the art that not even the whole collective mechanical skill of cylinder-making could furnish a bored cylinder of the simplest kind. This is not to be construed as unduly hard upon Glasgow, for it is said that all the skill of the world could not do so in 1765, only one hundred and forty years ago. We travel so fast that it is not surprising that there are wiseacres among us quite convinced that we are standing still. We may be pardoned for again emphasising the fact that it is not only for his discoveries and inventions that Watt is to be credited, but also for the manual ability displayed in giving to these "airy nothings "of the brain, a local habitation and a name," for his greatest idea might have remained an “airy nothing," had he not been also the mechanician able to produce it in the concrete. It is not, therefore, only Watt the inventor, Watt the discoverer, but also Watt, the manual worker, that stands forth. As we shall see later on, he created a new type of workmen capable of executing his plans, working with, and educating them often with his own hands. Only thus did he triumph, laboring mentally and physically. Watt therefore must always stand among the benefactors of men, in the triple capacity of discoverer, inventor, and constructor. The defects of the cylinder, though serious, were clearly mechanical. Their certain cure lay in devising mechanical tools and appliances and educating workmen to meet the new demands. An exact cylinder would leave no room for leakage between its smooth and true surface and the piston; but the solution of another difficulty was not so easily indicated. Watt having closed the top of the cylinder to save steam, was debarred from using water on the upper surface of the piston as Newcomen did, to fill the interstices between piston and cylinder and prevent leakage of steam, as his piston was round and passed through the top of the cylinder. The model leaked badly from this cause, and while engaged trying numerous expedients to meet this, and many different things for stuffing, he wrote to a friend, "My old White Iron "man is dead." This being the one he had trained to be his best mechanic, was a grievous loss in those days. Misfortunes never come singly; he had just started the engine after overhauling it, when the beam broke. Discouraged, but not defeated, he battled on, steadily gaining ground, meeting and solving one difficulty after another, certain that he had discovered how to utilise steam. |