THE SCIENTIST 173 



cation, stimulated by contact with the Cornish min- 

 ing industry, Davy pursued this new study with zeal, 

 and within a few months had written two essays full 

 of daring generalizations on the physical sciences. 

 These were published early in 1790. Partly on the 

 basis of the ingenious experiment mentioned in the 

 preceding chapter, he came to the conclusion that 

 " Heat, or that power which prevents the actual 

 contact of the corpuscles of bodies, and which is the 

 cause of our peculiar sensations of heat and cold, 

 may be defined as a peculiar motion, probably a vi- 

 bration, of the corpuscles of bodies, tending to sepa- 

 rate them." Other passages might be quoted from 

 these essays to show how the gifted youth of nineteen 

 anticipated the science of subsequent decades, but in 

 the main these early efforts were characterized by 

 the faults of overwrought speculation and incomplete 

 verification. He soon regretted the premature pub- 

 lication of his studies. " When I consider," he wrote, 

 " the variety of theories that may be formed on the 

 slender foundation of one or two facts, I am con- 

 vinced that it is the business of the true philosopher 

 to avoid them altogether. It is more laborious to 

 accumulate facts than to reason concerning them ; 

 but one good experiment is of more value than the 

 ingenuity of a brain like Newton's." 



In the mean time Davy had been chosen superin- 

 tendent of the Pneumatic Institution at Bristol by 

 Dr. Beddoes, its founder. It was supported by the 

 contributions of Thomas Wedgwood and other dis- 

 tinguished persons, and aimed at discovering by 

 means of experiment the physiological effect of in- 

 haling different gases, or " factitious airs," as they 



