In reality, the story of the discovery of the steam engine is far more inspiring. The history of the application of steam to human use is almost the history of science itself; the stages of its development are clearly marked for us; and the large succession of these stages, and the calibre of the minds which contributed to the achievement of the perfected steam engine, are some measure of the essential complexity of what is to-day regarded as a comparatively simple machine. For the steam engine was not the gift of any particular genius or generation; it did not leap from any one man’s brain. Some of the greatest names in the history of human knowledge can claim a share in its discovery. From philosopher to scientist, from scientist to engineer the grand idea was carried on, gradually taking more and more concrete form, until finally, in an age when by the diffusion of knowledge the labours of all three were for the first time co-ordinated, it was brought to maturity. A new force of nature was harnessed which wrought a revolution in the civilized world.
An attempt is made in this chapter to chronicle the circumstances under which the successive developments of the steam engine took place. The progress of the scientific ideas which led up to the discovery of the power of steam is traced. The claims of the various inventors chiefly associated with the steam engine are set forth in some detail, not for the difficult and invidious task of assessing their relative merits, but because by the light of these claims and altercations it may be possible to discern, in each case, where the merit lay and to what stage each novelty of idea or detail properly belonged. From this point of view, it is thought, the recital of circumstances which hitherto have been thought so trivial as to be scarcely worthy of record, may be of some suggestive value. The result of the investigation is to make clear the scientific importance of the steam engine: the steam engine regarded, not as the familiar drudge and commonplace servant of to-day, but in all its dignity of a thermodynamic machine, that scientific device which embodied so much of the natural philosophy of the age which first unveiled it—the seventeenth century.
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Before the Christian era steam had been used to do mechanical work. In a treatise, Pneumatica, written by Hero of Alexandria about 130 B.C., mention is made of a primitive reaction turbine, which functioned by the reactionary force of steam jets thrown off tangentially from the periphery of a wheel. In the same work another form of heat-engine is described: an apparatus in which, by the expansion from heating of air contained in a spherical vessel, water was expelled from the same vessel to a bucket, where by its weight it gave motion mysteriously to the doors of temples. And evidence exists that in these two forms heat engines were used in later centuries for such trivial purposes as the blowing of organs and the turning of spits. But except in these two primitive forms no progress is recorded for seventeen centuries after the date of Hero’s book. The story of the evolution of steam as a motive force really begins, with the story of modern science itself, at the end of the Middle Ages.
With the great revival of learning which took place in Southern Europe in the latter part of the fifteenth century new light came to be thrown on the classical philosophies which still ruled men’s minds, and modern science was born. New views on natural phenomena began to irradiate, and, sweeping aside the myths and traditions which surrounded and stifled them, the votaries of the “new science” began to formulate opinions of the boldest and most unorthodox description.[70] The true laws of the equilibrium of fluids, discovered originally by Archimedes, were rediscovered by Stevinus. By the end of the sixteenth century the nature of the physical universe was become a pursuit of the wisest men. To Galileo himself was due, perhaps, the first distinct conception of the power of steam or any other gas to do mechanical work; for “he, the Archimedes of his age, first clearly grasped the idea of force as a mechanical agent, and extended to the external world the conception of the invariability of the relation between cause and effect.”[71] To his brilliant pupil Torricelli the questioning world was indebted for the experiments which showed the true nature of the atmosphere, and for the theory he proclaimed that the atmosphere by its own weight exerted its fluid pressure—a theory which Pascal soon confirmed by the famous ascent of his barometer up the Puy-de-Dôme, which demonstrated that the pressure supporting his column of mercury grew less as the ascent proceeded. Giovanni della Porta, in a treatise on pneumatics published in the year 1601, had already made two suggestions of the first importance. Discussing Hero’s door-opening apparatus, della Porta showed that steam might be substituted for air as the expanding medium, and that, by condensing steam in a closed vessel, water might be sucked up from a lower level by virtue of the vacuum so formed. And a few years later, in 1615, Solomon de Caus, a French engineer, had come to England with a scheme almost identical with della Porta’s, and actually constructed a plant which forced up water to a height by means of steam. Shortly afterwards the “new science” received an accession of interest from the invention, by Otto von Guericke of Magdeburg, of a suction pump by which the atmospheric air could be abstracted from a closed vessel.
By the middle of this century the learned of all European countries had been attracted by the knowledge gained of the material universe. In England the secrets of science were attacked with enthusiasm under the new strategy of Lord Bacon, enunciated in his Novum Organum. The new philosophy was patronised by royalty itself, and studied by a company of brilliant men of whom the leading physicist was Robert Boyle, soon famous for his law connecting the volumes and the pressures of gases. In France, too, a great enthusiasm for science took birth. A group of men, of whom the most eminent was Christian Huyghens, banded themselves together to further scientific inquiry into the phenomena of nature and to demolish the reigning myths and fallacies: they also working admittedly by the experimental method of Bacon.
The time was ripe, however, for wider recognition of these scientists and the grand object of their labours. Within a short time the two groups were both given the charter of their respective countries; in France they were enrolled as the Royal Academy of Sciences; in England, as the Royal Society for Improving Natural Knowledge. In other countries societies of a similar kind were formed, but their influence was not comparable with that exerted by the societies of London and Paris. Between these two a correspondence was started which afterwards developed into one of the most famous of publications: the Philosophical Transactions. In England, especially, the Royal Society served from its inception as a focus for all the great minds of the day, and in time brought together such men as Newton, Wren, Hooke, Wallis, Boyle—not to mention his majesty King Charles himself; who, with the best intentions, could not always take seriously the speculations of the savants. “Gresham College he mightily laughed at,” noted Mr. Pepys in his diary for the first of February, 1663, “for spending time only in weighing of ayre, and doing nothing else since they sat.” A year later Pepys was himself admitted a member of the distinguished company, and found it “a most acceptable thing to hear their discourse, and see their experiments, which were this day on fire, and how it goes out in a place where the air is not free, and sooner out in a place where the ayre is exhausted, which they showed by an engine on purpose.”
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In the year 1663, just after the formation of the Royal Society, a small book was published by the Marquis of Worcester, A Century of the Names and Scantlings of such Inventions as he had tried and perfected.
Of these inventions one, the sixty-eighth, is thus described: