APPENDIX. 



RETRANSLATION OF AN HISTORICAL NOTE BY LORD 

 BROUGHAM, ON THE DISCOVERY OF THE COMPOSITION 

 OF WATER. 



THERE is no doubt that in England, at least, the researches 

 respecting the composition of water originated in Warltire's 

 experiments related in the fifth volume of Priestley.* Caven- 

 dish cites them expressly as having given him the idea of his 

 work (Phil. Trans. 1784, p. 126). Warltire's experiments con- 

 sisted in the combustion of a mixture of oxygen and hydrogen, 

 by means of the electric spark, and in closed vessels. Two re- 

 sults were reported therefrom: 1. a perceptible loss of weight; 

 2. the precipitation of some humidity on the sides of the vessels. 



Watt inadvertently said in the note to page 332, of his 

 Memoir (Phil. Trans. 1784), that the aqueous precipitation 

 was observed for the first time by Cavendish ; but Cavendish 

 himself declares, p. 127, that Warltire had perceived the slight 

 aqueous deposit, and quotes on this subject Priestley's fifth 

 volume. Cavendish could not ascertain any loss of weight. 

 He remarks that Priestley's essays had led him to the same 

 result ft and adds that the humidity which was deposited con- 



* Warltire's letter, dated Birmingham, 18th April, 1781, was pub- 

 lished by Dr. Priestley in the second volume of his Experiments and 

 Observations relating to various branches of Natural Philosophy, with a 

 continuation of the Observations on Air, forming, in short, the fifth 

 volume of the Experiments and Observations on different Kinds of Air, 

 published at Birmingham in 1781. (Note by Mr. Watt,jun.) 



t The note by Mr. Cavendish to p. 127, seems to imply that Priest- 



