318 Lord Brougham on the Composition of Water. 



tions were afterwards made to it. It was published in 1784. It con- 

 tained Mr Lavoisier's account of his experiments in June 1783, at which, 

 he says. Sir Charles Blagden was present ; and it states that he told Mr 

 Lavoisier of Mr Cavendish having " already burn t inflammable air in close 

 vessels, and obtained a very sensible quantity of water." But he, Mr 

 Lavoisier, says nothing- of Sir Charles Blagden having also mentioned Mr 

 Cavendish's conclusion from the experiment. He expressly states, that 

 the weight of the water was equal to that of the two airs burnt, unless 

 the heat and light which escape are ponderable, which he holds them not 

 to be. His account, therefore, is not reconcilable with Sir Charles Blag- 

 den's, and the latter was most probably written as a contradiction of it, 

 after Mr Cavendish's paper had been read, and when the Memoires of 

 the Acadeniie were received in this country. These Memoires were pub- 

 lished in 1784, and could not certainly have arrived when Mr Caven- 

 dish's paper was written, nor when it was read to the Royal Society. 



But it is further to be remarked, that the passage of Mr Cavendish's 

 paper in Sir Charles Blagden's handwriting, only mentions the experi- 

 ments having been communicated to Dr Priestley ; they were made, 

 says the .passage, in 1781, and communicated to Dr Priestley, it is not 

 said when, nor is it said that " the conclusions drawn from them," and 

 which Sir Charles Blagden says he communicated to Mr Lavoisier in 

 summer 1783, were ever communicated to Dr Priestley ; and Dr Priest- 

 ley in his paper (referred to in Mr Cavendish's), which was read June 

 1783, and written before April of that year, says nothing of Mr Ca- 

 vendish's theory, though he mentions his experiment. 

 Several propositions then are proved by this statement. 

 First, That Mr Cavendish in his paper, read 16th January 1784, relates 

 tlie capital experiment of burning oxygen and hydrogen gases in a close 

 vessel, and finding pure water to be the produce of the combustion. 



Secondly, That in the same paper, he drew from this experiment the 

 conclusion, that the two gases were converted or turned into water. 



Thirdly, That Sir Charles Blagden inserted in the same paper, with Mr 

 C;i vendish's consent, a statement that the experiment had first been made 

 by Mr Cavendish in summer 1781, and mentioned to Dr Priestley, though 

 it is not said when, nor is it said that any conclusion was mentioned to 

 Dr Priestley ; nor is it said at what time Mr Cavendish first drew that 

 conclusion. A most material omission. 



Fourthly, That, in the addition made to the paper bj' Sir Charles Blag- 

 den, the conclusion of Mr Cavendish is stated to be, that oxygen gas is 

 water deprived of phlogiston ; this addition having been made after Mr 

 Lavoisier's memoir arrived in England. 



It may further be observed, that in another addition to the paper, 

 which is in Mr Cavendish's handwriting, and which was certainly made 

 after Mr Lavoisier's memoir had arrived, Mr Cavendish for the first time 

 distinctly states^ as upon Mr Lavoisier's hypothesis, that water consists 

 of hydrogen united to oxygen gas. There is no substantial difference 



