NATURE 



m 



THURSDAY, AUGUST 25, 1881 



PAPIN 

 Dr. Ernst Gerlatid's Life a?id Letters of Papin. {Leib- 

 nizens' unci Huygens' Brie/weehsel mit Papin, ticbst 

 der Biograpliie Papin's, von Dr. Ernst Gerland. 

 Berlin, 1881.) 



AT a time when Britons have just been celebrating the 

 centenary of Stephenson a glance at the life and 

 works of one who in a much more accurate sense was tJie 

 inventor of the steam-engine may not be amiss. Denis 

 Papin, whose life and letters now appear from the editorial 

 pen of Dr. Ernst Gerland, was born at Blois in 1647. In 

 1661 or 1662 he proceeded to the study of medicine at the 

 University of Angers, and, receiving his degree in 1669, 

 he appears to have intended to settle down to a physi- 

 cian's life in that city. Why this course was not fulfilled 

 is not known ; but we find him in 1674 at Paris, where 

 also he had made the acquaintance of Huygens, with 

 whom he was engaged in experimenting with the newly- 

 discovered air-pump, an account of which was published 

 in that year at Paris under the title of " Expdriences du 

 Vuide." The Philosopliical Transactions of our Royal 

 Society for the following year (1675) were enriched by no 

 fewer than five papers on the same subject by Huygens 

 and Papin jointly. In Paris also Papin met Leibniz, who 

 sojourned there from 1672 to 1676. His acquaintance 

 with Leibniz was however interrupted, for, very shortly 

 after the publication of his " Expdriences," he crossed the 

 Channel to England, led, as Boyle tells us, by some hope 

 that here he might procure a situation accordant to his 

 genius. In London he assisted Boyle in his laboratory 

 and with his writings, and shortly afterwards introduced 

 into the air-pump the further improvement of making it 

 with double barrels, and replacing the turncock hitherto 

 used by the two valves. A little later he produced 

 another instrument, the condensing pump, and in 1680, 

 on Boyle's nomination, he was admitted to the distinction 

 of Fellowship in the Royal Society. That honour he re- 

 paid in the following year by communicating to the 

 Society his famous invention of "A new Digester or 

 Engine for Softening Bones," in which instrument — now 

 so universally known — he applied as it seems for the first 

 time the now common device of a safety-valve. For that 

 year and the next he devoted himself to experiments with 

 the digester and its various applications. Then he received 

 an invitation to proceed to Venice to take part in the work 

 of the Accademia di Scienze Filosofiche e Matematice, 

 then newly founded, in imitation of the learned societies of 

 Rome, Florence, Paris, and London. Here he appears 

 to have remained nearly two years, and early in 16S4 we 

 find him back again in London, where, on April 2, he was 

 elected by the Royal Society as their " temporary curator 

 of experiments," at a salary of 30/. per annum. This 

 was in the palmiest days of the young Society, when 

 Newton, Boyle, Hooke, Hawkesbee, and many other 

 famous spirits took the most active part in its proceed- 

 ings, and Papin shared in the work of bringing their 

 experiments, embracing a most miscellaneous range of 

 subjects, before the Society. Amongst the discoveries of 

 his own, of which Dr. Gerland gives a summary, in this 

 Vol. XXIV. — No. 617 



way brought before the Royal Society, was the so- 

 called Wurtemberg siphon. He also partially anticipated 

 Franklin in his discovery of the ebullition of water under 

 reduced pressure at lowered temperatures, concerning which 

 point he observes :" This shows that liquors being freed 

 from an external pressure will make bubbles upon the 

 score of the elastic particles lurking in their pores, as has 

 been observed long ago by the Hon. Mr. R. Boyle. I do 

 therefore believe that the vapours raised by heat in 

 an exhausted glass will make a pressure, which is 

 quickly taken off when we condense these vapours by 

 putting the glass into cold water or ice." On another 

 occasion Papin brought forward a model of a machine 

 for raising water by pumps to a height, the pumps being 

 worked by a water-wheel driven by the flow of a river. 

 In November, 1687, this occupation came to an end by 

 Papin resigning his post of curator on being appointed 

 by the Landgrave of Hesse to be Professor of Mathe- 

 matics at Marburg. Here the most active portion of 

 his life began, to be continued when, in 1696, his place of 

 residence was exchanged for Cassel. Here too began the 

 correspondence with Huygens and with Leibniz, which 

 forms the major part of the volume before us. By both 

 of these great men he was highly esteemed. Huygens 

 explained to him in 1690 his new theory of double refrac- 

 tion in a letter of considerable length. Leibniz wrote to 

 Luca about Papin, referring to his ingenious inventions 

 in the most enthusiastic terms. The correspondence with 

 Leibniz went on almost unbroken until Papin's final 

 return to England heart-broken and worn out. That 

 with Huygens ended much earlier, being terminated by 

 Huygens' premature decease in 1695. To Huygens in 

 1691 Papin writes from Cassel about a project he is un- 

 dertaking for the Landgrave, to construct a ship on the 

 plan suggested previously by Drcbbel to move under 

 water. In the same letter he mentions the production of 

 fog or mist in the receiver of the air-pump, for which 

 phenomenon Huygens, in replying, propounds an ex- 

 planation. At the same date we find Papin busy with 

 another invention, a rotilis sudor, which was nothing else 

 than a centrifugal fan for supplying a blast for furnaces 

 and for ventilating mines, which instrument he had the 

 satisfaction of applying to a mine in Germany in 1699, 

 and six years later he made the further improvements 

 related in the Phiiosophical Transactions of that year. 

 But his greater work was drawing on. In 169S he writes 

 to Leibniz that he is constructing a machine for raising 

 water to a great height by the force of fire, and that by 

 the success of his experiments he is persuaded that this 

 force can be applied to many other more important ends. 

 Leibniz replied forthwith with the inquiry whether his 

 invention was based upon the principle of rarefaction ; 

 adding that he also had some ideas on the point. After 

 two months Papin replies that he relies upon the prin- 

 ciple of rarefaction produced by the condensation of 

 steam, but that he proposes also to use the pressure ex- 

 erted by the steam in expanding, "the power of which is 

 not limited as is that of the suction " (of rarefaction). 

 He also says that he has made a little model of a car- 

 riage which is propelled by this force, but that he fears 

 difficulties for such carriages from the inequalities and 

 sharp turns of ordinary high roads — difficulties which for 

 water carriages do not exist. Leibniz's reply is only known 



