|The basics of the Papin steam engine: a piston and cylinder containing water that is made to expand in contract in cycles, by alternate contact with fire and water, cyclically, so as to produce useful work, outlined in prototype theory in 1690 by French physicist Denis Papin. |
This design was later used by English engineers Thomas Savery, in 1697, and Thomas Newcomen, in 1710, to make the first working steam engines. Soon more steam engines were built, generally being improved modifications of the Newcomen design. The study of the physics of these various heat engines was outlined in the 1823 memoir Reflections on the Motive Power of Fire by French physicist Sadi Carnot. This initiated the science of thermodynamics.
In his New Method, Papin begins with a discussion of the difficulties and failures involved in trying to create a vacuum in a piston and cylinder by means of gunpowder. In this mindset, he states that he had recently begun to endeavor to find a more functional way to create the vacuum. In particular, Papin reasons, "since it is a property of water, that a small quantity of it turned into vapor by heat has an elastic force like air, but upon cold supervening is resolved again into water, so that no trace of the said elastic force remains", he thus arrived at the view where:
“I at once saw that machines could be constructed, in which water, by the help of a moderate heat, and a little cost, might produce that perfect vacuum which could by no means be obtained by the aid of gunpowder.”
On this proposition, Papin states his design as such: “A is a tube of uniform diameter, closed shut at the bottom, B is a piston fitted to the tube; D a handle fixed to the piston; E an iron rod movable round an axis F; G a spring pressing the cross-rod E, so that the said rod must be forced into the groove H as soon as the piston with the handle has arrived at such a height as that the said groove H appears above the lid I; L is a little hole in the piston, through which the air can escape from the bottom of the tube A, when first the piston is forced into it.”
The use of this instrument, according to Papin, is as follows: “a small quantity of water is poured into the tube A, to the depth of three or four lines; then the piston is inserted and forced down to the bottom, till a portion of the water previously poured in comes through the hole L; then the said hole is closed by the rod M. Next the lid I, pierced with the apertures requisite for that purpose, is put on, and a moderate fire being applied, the tube A soon grows warm (being made of thin metal), and the water within it, being turned to steam, exerts a pressure so powerful as to overcome the weight of the atmosphere and force up the piston B, till the grove H of the handle D appears above the lid I, and the rod E is forced, with some noise, into the said groove by the spring G. Then forthwith the fire is to be removed, and the stream in the thin metal tube is soon resolved into water, and leaves the tube entirely void of air.”
Next, continues Papin, “the rod E being turned round so far as to come out of the groove H, and allow the handle D to descend, the piston B is forthwith pressed down by the whole weight of the atmosphere, and causes the intended movement; which is of an energy great in proportion to the size of the tube.”
Interestingly, this is one of the first modern utilizations of the term “energy” in a physics sense; predating 1807 kinetic energy definition of English physicist and physician Thomas Young, being rather a precursor of sorts to German physicist Rudolf Clausius’ 1850 formulation of the “internal energy” U of the working body.
In terms of experimental results, Papin states that his tube was 2.5-inches in diameter, it raised 60-pounds, and that 1-minute was sufficient for a moderate fire to drive the piston to the top.
He proposed to apply this power to draw water or ore from mines; to discharge iron bullets to a great distance; to propel ships against the wind (using an arrangement of paddle-wheels); and to other practical applications. An account of his steam engine design was included in a small treatise published by Papin, both in Latin and French, at Marburg and Cassel respectively, in 1695.  In 1698, Papin published a work titled Treatise of Several New Machines and Extraordinary Inventions on Different Topics.  Papin, however, never made a working model.
Influence in England
Soon enough, Papin’s design for a steam engine found their way to England. Specifically, a brief notice of Papin’s steam engine designs were included in the Philosophical Transactions for the year 1697, in a review of the little 1695 book published on the Continent by Papin.  The first to have come in contact with the work of Papin, it seems, was English engineer Thomas Newcomen.  In a communication on the subject from a Dr. Robinson, in reference to Robert Hooke (Dr. Hook), the noted polymath assistant of Robert Boyle who had previously designed a modified air vacuum-pump in 1657 and who later became the curator of experiments of the Royal Society from 1662 to 1703, we find: 
“There are to be found among Hook’s papers, in the possession of the Royal Society, some notes of observations, for the use of Newcomen, his countryman, on Papin’s boasted method of transmitting to a great distance the action of a mill by means of pipes … it would appear from these notes that Dr. Hook had dissuaded Mr. Newcomen from erecting a machine on this principle, of which he had exposed the fallacy in several discourse before the Royal Society. One passage is remarkable: ‘Could he (meaning Papin) make a speedy vacuum under your second piston, your work is done.’ ”
Although the exact date of this note is not known, it can be assigned to the period between 1687, the year when Papin proposed a plan of working an atmospheric engine at a distance by exhausting air through pipes, and March 1703 the time of Hooke's death.  This period in which Newcomen first began to devote his attention to the subject can be further refined. Author Stephen Switzer, in 1729, surmised “I am well informed that Mr. Newcomen was as early in his invention as Mr. Savery was in his, only the latter being nearer the Court had obtained his patent before the other knew it; on which account Mr. Newcomen was glad to come in as a partner to it.  As Savery obtained his first patent for his "Miner's Friend" (first working steam engine) on July 25, 1698, it follows that Newcomen would have already been contemplating an atmospheric steam engine prior to this time. It would thus seem likely that Newcomen became engaged in steam engine designs after reading the account of Papin’s proposal in the 1697 Philosophical Transactions, if not before in 1695 or 1690, through his association with his countryman Robert Hooke, associate of Robert Boyle, an associate of Papin. 
1. (a) Papin, Denis. (1690). “A New Way to Obtain Very Great Motive Powers at Small Cost” (Nova Methodus ad Vires Motrices Validissimas levi Pretio Comparandas). Acta Eruditorum, anno, Aug., pgs. 410-14.
(b) Muirhead, James. (1859). The Life of James Watt, (English translation: Ch. XI, Denys Pain: His memoir of 1690, Section: A New Way to Obtain Very Great Motive Powers at Small Cost”, pgs. 131-42). London: John Murray.
(c) The original Latin, accompanied by a translation, in Muirhead’s Mechanical Inventions of James Watt, Vol. III., pg. 139.
2. Galloway, Robert L. (1881). The Steam Engine and its Inventors. London: MacMillan and Co.
3. (a) Papin, Dionysio. (1695). Fasiculus Disscrtationum de Novis Quibusdam Machinis, &c., Marburgi Cattorum.
(b) Papin, Dionysio. (1695). Recueil de Diverses Pieces Touchant Quelques Nouvelles Machines (Various European Pieces With Some New Machines). Cassel.
4. Papin, Dionysio. (1698). Traite de Plusieurs Nouvelles Machines et Inventions Extraordinaires sur Differents Sujets (Treatise of Several New Machines and Extraordinary Inventions on Different Topics). Paris.
5. Phil. Trans. 1695, No. 226, pg. 481.
6. A System of Mechanical Philosophy, by John Robinson, LL.D., with Notes, by David Brewster, LL.D., Edinburgh, 1822, Vol. II., pg. 57.
7. Switzer, Stephen. (1729). An Introduction to a General System of Hydrostaticks and Hydraulicks, &c., Vol. II., pg. 342. London.