350 Analysis of Books. 



light and heat, which had produced a favourable impression, and 

 after some little negotiation, he was engaged ; his mother yielded 

 to his wishes ; and Mr. Borlace generously surrendered his inden- 

 ture, indorsing upon it, that he freely gave it up * on account of the 

 singularly promising talents which Mr. Davy had displayed.' He, 

 however, so offended his old friend, Mr. Tonkin, by this measure, 

 that he revoked the legacy of his house, which he had previously 

 bequeathed him, in contemplation of fixing him in his native 

 town as a surgeon. Davy quitted Penzance for Bristol in high 

 spirits, in October, 1798, before he had attained his twentieth year. 

 His position was now extremely favourable to the development of 

 his genius. He was constantly engaged in the prosecution of new 

 experiments, in the conception of which he was greatly aided by 

 Dr. Beddoes, and occasionally assisted by Mr. Clayfield, to whom 

 he was indebted for the invention of a mercurial air-holder, by 

 which he was enabled to collect, measure, and examine the various 

 gases. He enjoyed at Bristol the advantage of intellectual society ; 

 among others with whom he was intimate, were Mr. Edgeworth, 

 and James Tobin, the author of the Honey Moon. The present 

 Lord Durham and his brother were then also resident in the house 

 of Dr. Beddoes. With some of these eminent persons Davy con- 

 tracted permanent friendships. Dr. Paris says, ' there was more 

 than one avenue to his heart ; and the philosopher, the poet, the 

 physician, the philanthropist, and the sportsman, found each, upon 

 different terms, a more or less ready access to its recesses ; but the 

 fisherman instantly caught his affections.' ' To be a fly-fisher was, 

 in his opinion, to possess the capabilities of intellectual distinction, 

 though circumstances might not have conspired to call them into 

 action.' It has been asserted by those who knew him through life, 



* that his extraordinary talents never at any period excited greater 

 astonishment than during his residence at Bristol.' 



At the commencement of 1799, Dr. Beddoes published a work 

 under the title of ' Contributions to Physical and Medical Know- 

 ledge, principally from the West of England ;' nearly one-half of 

 the volume consists of essays by Davy : ' On Heat, Light, and the 

 Combinations of Light ;' 'On Phos-oxygen, or Oxygen and its 

 Combinations ;' and * On the Theory of Respiration.' 



' In his chapter on Light and its Combinations,' says his biographer, 



* he indulges in speculations of the wildest nature, although it must be 

 confessed that he has infused an interest into them which might be 

 almost called dramatic. His first essay commences with an experiment 

 in order to show that light is not, as Lavoisier supposed, a modification, 

 or an effect of heat ; but matter of a peculiar kind, sui generis, which, 

 when moving through space, or in a state of projection, is capable of 

 becoming the source of a numerous class of our sensations. With 

 regard to caloric his opinion was, that it is not, like light, material ; and 

 he maintains the proposition by the same method of reasoning as that by 

 which he attempts to establish the materiality of light, and which mathe- 

 maticians have termed the reductio ad absurdum.' 



