James Fyfe - Triumphs of Invention and Discovery in Art and Science

In tracing this lineage of inventive genius, we next come to Thomas Newcomen, a blacksmith, who carried out the principle of the piston in his Atmospheric Engine, for which he took out a patent in 1705. It is but just to recognize that this engine was the first which proved practically and widely useful, and was, in truth, the actual progenitor of the present steam engine. It was chiefly used for working pumps. To one end of a beam moving on a central axis was attached the rod of the pump to be worked; to the other, the rod of the piston moving in the cylinder below. Underneath this cylinder was a boiler, and the two were connected by a pipe provided with a stop-cock to regulate the supply of steam. When the pump-rod was depressed, and the piston raised to the top of the cylinder, which was effected by weights hanging to the pump-end of the beam, the stop-cock was used to cut off the steam, and a supply of cold water injected into the cylinder through a water-pipe connected with the tank or cistern. The steam in the cylinder was immediately condensed; a vacuum created below the piston; the latter was then forced down by atmospheric pressure, bringing with it the end of the beam to which it was attached, and raising the other along with the pump-rod. A fresh supply of steam was admitted below the piston, which was raised by the counterpoise; and thus the motion was constantly renewed. The opening and shutting of the stop-cocks was at first managed by an attendant; but a boy named Potter, who was employed for this purpose, being fonder of play than work, contrived to save himself all trouble in the matter by fastening the handles with pieces of string to some of the cranks and levers. Subsequently, Beighton, an engineer, improved on this idea by substituting levers, acted on by pins in a rod suspended from the beam.

Properly speaking, Newcomen's engine was not a steam, but an atmospheric engine; for though steam was employed, it formed no essential feature of the contrivance, and might have been replaced by an air-pump. All the use that was made of steam was to produce a vacuum underneath the piston, which was pressed down by the weight of the atmosphere, and raised by the counterpoise of the buckets at the other end of the beam. Watt, in bringing the expansive force of steam to bear upon the working of the piston, may be said to have really invented the steam engine. Half a century before the little model came into Watt's hands, Newcomen's engine had been made as complete as its capabilities admitted of; and Watt struck into an entirely new line, and invented an entirely new machine, when he produced his Condensing Engine.

There are few places in our country where human enterprise has effected such vast and marvellous changes within the century as the country traversed by the river Clyde. Where Glasgow now stretches far and wide, with its miles of swarming streets, its countless mills, and warehouses, and foundries, its busy ship-building yards, its harbour thronged with vessels of every size and clime, and its large and wealthy population, there was to be seen, a hundred years ago, only an insignificant little burgh, as dull and quiet as any rural market-town of our own day. There was a little quay at the Broomielaw, seldom used, and partly overgrown with broom. No boat over six tons' burden could get so high up the river, and the appearance of a masted vessel was almost an event. Tobacco was the chief trade of the town; and the tobacco merchants might be seen strutting about at the Cross in their scarlet cloaks, and looking down on the rest of the inhabitants, who got their livelihood, for the most part, by dealing in grindstones, coals, and fish – "Glasgow magistrates," as herrings are popularly called, being in as great repute then as now. There were but scanty means of intercourse with other places, and what did exist were little used, except for goods, which were conveyed on the backs of pack-horses. The caravan then took two days to go to Edinburgh – you can run through now between the two cities in little more than an hour. There is hardly any trade that Glasgow does not prosecute vigorously and successfully. You may see any day you walk down to the Broomielaw, vessels of a thousand tons' burden at anchor there, and the custom duties which were in 1796 little over £100, have now reached an amount exceeding one million!

Glasgow is indebted, in a great part, for the gigantic strides which it has made, to the genius, patience, and perseverance of a man who, in his boyhood, rather more than a hundred years ago, used to be scolded by his aunt for wasting his time, taking off the lid of the kettle, putting it on again, holding now a cup, now a silver spoon over the steam as it rose from the spout, and catching and counting the drops of water it fell into. James Watt was then taking his first elementary lessons in that science, his practical application of which in after life was to revolutionize the whole system of mechanical movement, and place an almost unlimited power at the disposal of the industrial classes.

When a boy, James Watt was delicate and sickly, and so shy and sensitive that his school-days were a misery to him, and he profited but little by his attendance. At home, though, he was a great reader, and picked up a great deal of knowledge for himself, rarely possessed by those of his years. One day a friend was urging his father to send James to school, and not allow him to trifle away his time at home. "Look how the boy is occupied," said his father, "before you condemn him." Though only six years old, he was trying to solve a geometrical problem on the floor with a bit of chalk. As he grew older he took to the study of optics and astronomy, his curiosity being excited by the quadrants and other instruments in his father's shop. By the age of fifteen he had twice gone through De Gravesande's Elements of Natural Philosophy, and he was also well versed in physiology, botany, mineralogy, and antiquarian lore. He was further an expert hand in using the tools in his father's workshop, and could do both carpentry and metal work. After a brief stay with an old mechanic in Glasgow, who, though he dignified himself with the name of "optician," never rose beyond mending spectacles, tuning spinets, and making fiddles and fishing tackle, Watt went at the age of eighteen to London, where he worked so hard, and lived so sparingly in order to relieve his father from the burden of maintaining him, that his health suffered, and he had to recruit it by a return to his native air. During the year spent in the metropolis, however, he managed to learn nearly all that the members of the trade there could teach, and soon showed himself a quick and skilful workman.

In 1757 we find the sign of "James Watt, Mathematical Instrument Maker to the College," stuck up over the entrance to one of the stairs in the quadrangle of Glasgow College. But though under the patronage of the University, his trade was so poor, that thrifty and frugal as he was, he had a hard struggle to live by it. He was ready, however, for any work that came to hand, and would never let a job go past him. To execute an order for an organ which he accepted, he studied harmonics diligently, and though without any ear for music, turned out a capital instrument, with several improvements of his own in its action; and he also undertook the manufacture of guitars, violins, and flutes. All this while he was laying up vast stores of knowledge on all sorts of subjects, civil and military engineering, natural history, languages, literature, and art; and among the professors and students who dropped into his little shop to have a chat with him, he soon came to be regarded as one of the ablest men about the college, while his modesty, candour, and obliging disposition gained him many good friends.

Among his multifarious pursuits, Watt had experimented a little in the powers of steam; but it was not till the winter of 1763-4, when a model of Newcomen's engine was put into his hands for repair, that he took up the matter in earnest. Newcomen's engine was then about the most complete invention of its kind; but its only value was its power of producing a ready vacuum, by rapid condensation on the application of cold; and for practical purposes was neither cheaper nor quicker than animal power. Watt, having repaired the model, found, on setting it agoing, that it would not work satisfactorily. Had it been only a little less clumsy and imperfect, Watt might never have regarded it as more than the "fine plaything," for which he at first took it; but now the difficulties of the task roused him to further efforts. He consulted all the books he could get on the subject, to ascertain how the defects could be remedied; and that source of information exhausted, he commenced a series of experiments, and resolved to work out the problem for himself. Among other experiments, he constructed a boiler which showed by inspection the quantity of water evaporated in a given time, and thereby ascertained the quantity of steam used in every stroke of the engine. He found, to his astonishment, that a small quantity of water in the form of steam heated a large quantity of water injected into the cylinder for the purpose of cooling it; and upon further examination, he ascertained the steam heated six times its weight of well water up to the temperature of the steam itself (212°). After various ineffectual schemes, Watt was forced to the conclusion that, to make a perfect steam engine, two apparently incompatible conditions must be fulfilled – the cylinder must always be as hot as the steam that came rushing into it, and yet, at each descent of the piston, the cylinder must become sufficiently cold to condense the steam. He was at his wit's end how to accomplish this task, when, as he was taking a walk one afternoon, the idea flashed across his mind that, as steam was an elastic vapour, it would expand and rush into a previously exhausted place; and that, therefore, all he had to do to meet the conditions he had laid down, was to produce a vacuum in a separate vessel, and open a communication between this vessel and the cylinder of the steam-engine at the moment when the piston was required to descend, and the steam would disseminate itself and become divided between the cylinder and the adjoining vessel. But as this vessel would be kept cold by an injection of water, the steam would be annihilated as fast as it entered, which would cause a fresh outflow of the remaining steam in the cylinder, till nearly the whole of it was condensed, without the cylinder itself being chilled in the operation. Here was the great key to the problem; and when once the idea of separate condensation was started, many other subordinate improvements, as he said himself, "followed as corollaries in rapid succession, so that in the course of one or two days the invention was thus far complete in his mind".