EARLY HISTORY OF THE ROYAL SOCIETY 



known in connection with the digester which bears his 

 name, and as a necessary adjunct to which, he invented 

 the safety valve. Papin gave a supper, prepared by his 

 digester, to some Fellows of the Society. Evelyn, who 

 was present, says in his Diary : ' The hardest bones of 

 beef and mutton were made as soft as cheese, ... a 

 jelly made of the bones of beef the most delicious I have 

 ever tasted; . . . this philosophical supper caused much 

 mirth amongst us, and exceedingly pleased all the com- 

 pany. ... I sent a glass of the jelly to my wife, to the 

 reproach of all that the ladies ever made of the best harts- 

 horn." 



Papin observed that the boiling point of water becomes 

 higher when under pressure from its own steam ; and in 

 1687 he proposed to use steam as a moving power for 

 draining mines, and later for propelling boats. His plan 

 consisted of a cylinder in which a piston is raised by the 

 expansion of the steam, and then is forced down by atmo- 

 spheric pressure in consequence of the vacuum produced 

 by the condensation of the steam. Papin was thus the 

 inventor of the earliest cylinder and piston steam-engine, 

 which afterwards took practical shape in the atmospheric 

 engine of Newcomen. 



The general scope of the early work of the Society is 

 manifest from the Committees appointed in 1664 to take 

 charge of some special branches of Natural Knowledge. 



I. Mechanical. (69 names.) 



II. Astronomical and Optical. (15.) 



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