272 M. Arago's Biographical Memoir of James Watt. 



is however now clearly established, that the paper referred to, 

 was read many months subsequent to the memoir in which 

 Cavendish alludes to it. 



Appearing upon this field of controversy, Blagden announces 

 his firm determination to clear up and settle every thing. He 

 does not flinch from any accusation, or from the citation of any 

 date, so long as his object is to insure for his protector and 

 friend Cavendish, the priority in reference to the French 

 chemist. So soon, however, as he takes up the question as 

 between his own two countrymen, his explanations become al- 

 together vague and obscure, " During the spring," he remarks, 

 " of the year 1783, Mr Cavendish shewed us that he had neces- 

 sarily deduced from his experiments, the conclusion, that oxygen 

 is nothing else than water deprived of its phlogiston (that is 

 to say, its hydrogen). About the same time, the news reached 

 London, that Mr Watt of Birmingham had been led by some 

 observations to a similar opinion." The expression. About the 

 same time, to adopt Mr Blagden's own phrase, was not the whole 

 truth. About the same time decides nothing. Questions of 

 priority may depend upon months, weeks, days, or even mi- 

 nutes. To be clear and precise, as he had promised, he ought 

 to have told us if the verbal communication made by Caven- 

 dish to several members of the Royal Society, preceded, or 

 followed, the reception of the news of Watfs opinion. Is it 

 conceivable that Blagden would have failed to be explicit upon 

 a fact of such importance, if he could have cited an authentic 

 date in favour of his friend I 



To make the confusion complete, even the compositors, 

 printers, and correctors of the press of the Philosophical Trans- 

 actions would appear to have taken part in the dispute. Many 

 of the dates are there inaccurately given. In the separate co- 

 pies of his memoir, which Cavendish himself distributed, I per- 

 ceive a mistake of a whole year. By a sad fatality, for it is a 

 real misfortune involuntarily to give occasion to grievous and 

 unmerited suspicions, not one of these typographical errors 

 was favourable to Watt ! Let it not be supposed that, by 

 these remarks, I mean to inculpate the literary honesty of the 

 celebrated men whose names I have mentioned ; they prove 

 merely, that where matters of discoveiy are concerned, the 



