250 DESCRIPTION' OF AN AIR ENGINE. 



sue it with success, those of Petersburg, Wilua, Copenha- 

 gen, and Stockholm, to investigate this point of natural his- 

 tory. 

 Wars have no- To this political circumstances can be no obstacle. There 

 wl'hfilies^i- ^^ never \var between the learned, between academies. Nei- 

 ences. ther our emperor nor the kino; of England has disapproved 



your communicating with the royaj society of London for 

 the interests of the sciejiccs. Scientific voyages have been 

 respected by both parries. In the electorate of Hanover the 

 university of Gottingen was protected by our army. The 

 republic of letters, that great and noble benefactress of all 

 polished states, ever preserves its honourable and friendly 

 neutrality. 



Suspended Already many of those who happen to be drowned, orsuf- 



animation of r ^ ^ , , . ., . ,,> „,. 



drowned and located by carbonic acid, are. restored to life. Ihese arc 



suffocated per- two provinces, which Humanity has conquered from thft 

 sons- already . /• tn i ^ ' . . . ^ , . , . ,. 



testored. empire ot Death at the two extremities of his domain: for 



these two diseases, so long considered as deaths, are totally 



different in their nature, and require opposite means of 



cure. 



Those princes, who dispute with each other the territories 



of the living^ see with regret by how many murders they 



must be purchased : they would be the first to encourage the 



peaceful labours and fraternal correspondence, that might 



conduce to recover from the yet' doubtful bonds of death a 



third class of its victims, men benumbed by frost. 



IV. 



Description of an Engine for affording Mechanical Power 

 from Air expanded by Heat; hy Sir George Cayley, Bart, 



To Mr. NICHOLSON. 



Sir, Brompton, Sept. 25, 1807. 



E^^pan^ion of JL Observed in your last vol. p. 368, thatsome experiment* 



air by heat ^^^^ 1^^^^^ lately made in Fiance upon air, expanded by 

 considered as a •' ^ , '^ . 



first mover. heat, applied as a ^rst naover tiar raechamcal purposes. 1 his 



idea. 



