“An admirable and most forcible way to drive up water by fire, not by drawing or sucking it upwards, for that must be as the Philosopher calleth it, Intra sphæram activitatis, which is but at such a distance. But this way hath no bounder, if the vessels be strong enough; for I have taken a piece of a whole cannon, whereof the end was burst, and filled it three-quarters full of water, stopping and screwing up the broken end, as also the touch-hole; and making a constant fire under it, within twenty-four hours it burst and made a great crack. So that having a way to make my vessels, so that they are strengthened by the force within them, and the one to fill after the other; I have seen the water run like a constant fountain-stream forty foot high; one vessel of water rarified by fire driveth up forty of cold water. And a man that tends the work is but to turn two cocks, that one vessel of water being consumed, another begins to force and refill with cold water, and so successfully, the fire being tended and kept constant, which the selfsame person may likewise abundantly perform in the interim between the necessity of turning the said cocks.”
On this evidence the claim is made that the marquis was the original inventor of the steam engine. Is he at all entitled to the honour? The whole affair is still surrounded with mystery. It is known that he was an enthusiastic student of physical science, and that for years he had working for him a Dutch mechanic, Caspar Kaltoff; it seems certain that he actually made a water-pumping engine worked by steam, of whose value he was so impressed that he promised to leave the drawings of it to Gresham College and intended to have a model of it buried with him.[72] But neither model nor drawings has ever yet been traced. And, considering the social influence of the inventor and the importance of the invention, the silence of his contemporaries on the discovery is strange and inexplicable. He received a patent for some form of water-pumping engine. Distinguished visitors came to Vauxhall to see his engine at work. He numbered among his acquaintances Sir Jonas Moore, Sir Samuel Morland, Flamstead and Evelyn: probably Mr. Pepys, Sir W. Petty, and others of the group of eminent men of his time who were interested in natural science. Yet no trace of his inventions has come down to us. His Century was admittedly compiled from memory—“my former notes being lost”—and perhaps it was designedly obscure; science was at that time a hobby of the cultured few, and scientific men loved to mystify each other by the exhibition, without explanation, of paradoxes and toys of their own construction. The marquis, it will be agreed, left valuable hints to later investigators. Whether his claim to have invented the steam engine is sufficiently substantiated, we leave to the opinion of the interested reader, who will find most of the evidence on this subject in Dirck’s Life of the Marquis of Worcester.
The power of steam to drive water from a lower to a higher level had been shown by Solomon de Caus,[73] who, in his work, Les Raisons des Forces Mouvantes, published in A.D. 1615, had described a hot-water fountain operated by heating water in a globe. In Van Etten’s Récreation Mathematique of 1629 was an experiment, described fifty years later by Nathaniel Nye in his Art of Gunnery as a “merry conceit,” showing how the force of steam could be used to discharge a cannon. As the century advanced the ornamental was gradually superseded by the utilitarian; the usefulness of steam for draining fens, pumping out mines, was realized; and applications for patents to cover the use of new and carefully guarded inventions began to appear.
Gunpowder as a medium was a strong competitor of steam. In 1661 King Charles granted to Sir Samuel Morland, his master of mechanics, “for the space of fourteen years, to have the sole making and use of a new invention of a certain engine lately found out and devised by him, for the raising of water out of any mines, pits, or other places, to any reasonable height, and by the force of air and powder conjointly.” What form the engine took is not known; whether the gunpowder was used to produce a gaseous pressure by which the work was done, or whether its function was to displace air and thus cause a vacuum as its gases cooled. In France, too, efforts were made at this time to produce a gunpowder engine. In 1678 a Jean de Hautefeuille raised water by gunpowder, but authorities differ as to whether he employed a piston—which were then in use as applied to pumps—or whether he burned the powder so that the gases came in actual contact with the water. In the following year an important advance was made. Huyghens constructed an engine having a piston and cylinder, in which gunpowder was used to form a vacuum, the atmospheric pressure providing the positive force to produce motion; and in 1680 he communicated to the Academy of Sciences a paper entitled, “A new motive power by means of gunpowder and air.”
But it was to his brilliant pupil, Denis Papin, that we are indebted for a further step in the materialization of the steam engine. Papin suggested the use of steam for gunpowder.
In 1680 Papin, who like Solomon de Caus had brought his scientific conceptions to England in the hope of their furtherance, was admitted on the recommendation of Boyle to a fellowship of the Royal Society. After a short absence he returned to London in ’84 and filled for a time the post of curator to the society, meeting, doubtless, in that capacity the leading scientists of the day and coming in touch with all the practical efforts of English inventors. During his stay here he worked with enthusiasm at the production of a prime mover, and when he left in ’87 for a mathematical professorship in Germany he continued there his researches and experienced repeated failures. In a paper published in ’88 he showed a clear conception of a reciprocating engine actuated by atmospheric pressure, and in ’90 he suggested for the first time the use of steam for forming the vacuum required. As water, he wrote, has elasticity when fire has changed it into vapour, and as cold will condense it again, it should be possible to make engines in which, by the use of heat, water would provide the vacuum which gunpowder had failed to give. This memorable announcement gave a clear direction to the future development of the heat engine. Steam was the medium best suited for utilizing the expansive power of heat generated by the combustion of fuel; steam was the medium which, by its expansive and contractile properties, could be made to impart a movement de va et vient to a piston. Though Papin did not succeed in putting his idea into practical form his conception was of great value, and he must be counted as one of the principal contributors to the early development of the steam engine. His life was an accumulation of apparent failures ending in abject poverty. To-day he is honoured by France as the inventor of the steam engine, and at Blois a statue has been erected and a street named to his memory.
Before the end of the century an effective engine had been produced, in England.
In 1698 Thomas Savery, a Devonshire man, obtained a patent for “a new invention for raising of water and occasioning motion to all sorts of millwork by the impellent force of fire.” Before the king at Hampton Court a model of this invention was displayed, and the importance of the new discovery was soon realized by the landed classes; for in the following year an act of parliament was passed for the encouragement of the inventor and for his protection in the development of what, it was recognized, was likely to prove of great use to the public. In the same year Savery published a pamphlet called The Miner’s Friend, and republished it, with additions, in 1702. This pamphlet contained a full and clear description of his engine; but significance has been attached to the omission from it of any claim that it embodied a new idea. The omission may be accidental.
The steam engine, shown in the accompanying illustration, was simply a pump, whose cycle of operations was as follows. Steam, admitted into the top of a closed vessel containing water and acting directly against the water, forced it through a pipe to a level higher than the vessel itself. Then, the vessel being chilled and the steam in it thereby condensed, more water was sucked into the vessel from a lower level to fill the vacuum thus formed; this water was expelled by steam in the same way as before, cocks being manipulated, and, eventually, self-acting valves being placed, so as to prevent the water from returning by the way it came. Two chambers were used, operating alternately.
For this achievement Savery is by many regarded as the first and true inventor. He certainly was the first to make the steam engine a commercial success, and up and down the country it was extensively used for pumping water and for draining mines. By others Savery was regarded as a copyist; and indeed it is difficult to say how far originality should be assigned him. The marquis too had claimed to raise water; his engine had evidently acted with a pair of displacement-chambers, from each of which alternately water was forced by steam while the other vessel was filling. And if he did not specify or appreciate the effect of the contractile force of the steam when condensed, yet in this respect both inventors had been anticipated by Giovanni della Porta.