Biographical Memoir of Sir Humphry Davy. 5 



fit him to converse on the subject with one well versed in its 

 principles. Some one to whom he mentioned his intention, pr(\- 

 cured for him an English translation of Lavoisier's chemistry. 

 In two days he had made himself completely master of it, and 

 it is very remarkable, that, in entire ignorance of the objections 

 which Priestley and others of his countrymen had raised against 

 the theory advanced in that celebrated work, he declared that 

 there occurred to him another explanation of the phenomena ; 

 and he began seriously to engage in developing it. The ani- 

 mated discussions which he had with Mr Watt on this subject, 

 had only the effect of confirming his resolution ; the poet and 

 the metaphysician decided at once on becoming a chemist. 

 The state of his affairs was such, as to render it no easy matter 

 to procure even the requisite instruments ; but in this, as in 

 every thing else that he undertook, his courage and perseve- 

 rance surmounted all obstacles. Old tobacco-pipes, and a few 

 glass-tubes purchased from a travelling vender of barometers, 

 formed his first apparatus. The surgeon of a French ship, 

 stranded near Land's End, shewed him his instruments, and 

 having observed a utensil of very common and familiar use 

 among us, the form of which apparently differs in the two 

 countries, he conceived the possibility of rendering it the princi- 

 pal piece in a pneumatic machine ; and to this purpose, so dif- 

 ferent from that for which it was intended, it was in reality ap- 

 plied. It is thus that, in the case of many great men, priva- 

 tion has proved the most useful master. 



The experience which he acquired on this occasion was never 

 afterwards lost. During his whole life, Mr Davy never wanted 

 a resource in his investigations ; the simplicity of his apparatus 

 was always as remarkable as the originality of his experiments, 

 and the elevation of his views ; and even when he travelled into 

 places the most remote from scientific aid, he was never more 

 at a loss to bring to the test of experiment any new idea that 

 occurred to him, than he was when he commenced his first la- 

 bours in the shop of his master at Penzance. 



After some further exercise, he took from his own neighbour- 

 hood the subject of his first experiment. He wished to ascer- 

 tain with what kind of air the vesicles of fuci are filled, and de- 

 termined, with as much precision as the most accomplished che 



