LORD UROUGHAM's APPENDIX. 471 



whole of the inflammable air lose their elasticity, and form by 



their condensation the dew that covers the glass On 



examining the dew, Cavendish found that it consisted of pure 

 ■water He thence concluded that nearly all the in- 

 flammable air and about one sixth of the common air are 

 turned into pure water." 



In a similar way, Cavendish burned a mixture of inflam- 

 mable air, and dephlogisticated air (or hydrogen and oxygen) ; 

 the fluid that was jirecipitated was always more or less acid, 

 according as the gas burned with the inflammable air contained 

 more or less phlogiston. The acid thus engendered was nitric 

 acid. 



Mr. Cavendish ascertained that nearly the whole of the in- 

 flammable air and the dephlogisticated air are converted into 

 pure water ; also, that if those airs could be obtained in a per- 

 fectly pure state, the whole would be condensed. If common 

 air and inflammable air do not yield any acid when they are 

 burnt, it is, according to our author, because the heat is not 

 then intense. 



Cavendish declares that his experiments, except in as far as 

 they relate to the acid, were made in the summer of 1781, 

 and that Priestley was aware of them. He adds, " One of my 

 friends gave some account of them to Lavoisier, in the course 

 of last spring (the spring of 1783), and also of the result that 

 I had inferred from them, that is to say, that dephlogisticated 

 air is water deprived of its phlogiston. But at that time, La- 

 voisier was so far from thinking that such a opinion was legiti- 

 mate, that until the moment when he determined to repeat 

 the experiments himself, he felt some difficulty in believing 

 that nearly the whole of the two airs could be converted into 

 water." 



The friend alluded to in the preceding passage was Dr., 

 since become Sir Charles Blagden. It is a remarkable cir- 

 cumstance, that this passage in the work of Mr. Cavendish 

 should not have formed part of the original Memoir that was 

 presented to the Royal Society. The Memoir seems to be 

 written in the author's own handwriting ; but the paragraphs 



