^ RELATION TO THE QUESTION. XXVU 



takes to make the dynamical theory of heat an English monopoly, 

 due to Sir Isaac Newton, Sir Humphrey Davy, and Dr. J. P. 

 Joule ; while an able writer in a late number of the North British 

 Review, in sketching the historic progress of the new views, puts 

 Davy forward as their founder, and assigns to Rumford a minor 

 and subsequent place. 



Sir Humphrey Davy, it is well known, early rejected the caloric 

 hypothesis. In 1799, at the age of twenty-one, he published a 

 tract at Bristol, describing some ingenious experiments upon the 

 subject. It was the publication of this pamphlet which brought 

 him to Eumford's notice, and resulted in his subsequent connection 

 with the Royal Institution. But Davy's ideas upon the question 

 were far from clear, and will bear no comparison with those of 

 Rumford, published the year before. Indeed his eulogist remarks : 

 "It is certain that even Davy himself was led astray in his argu- 

 ment by using the hypothesis of change of capacity as the basis 

 of his reasoning, and that he might have been met successfully by 

 any able calorist, who, though maintaining the materiality of heat, 

 might have been willing to throw overboard one or two of the less 

 essential tenets of his school of philosophy." It was not till 1812 

 that Davy wrote in his Chemical Philosophy, " The immediate 

 cause of the phenomena of heat then is motion, and the laws of its 

 communication are precisely the same as those of the communica- 

 tion of motion." "When, therefore, we remember that Davy's first 

 publication was subsequent to that of Rumford's, that he confined 

 himself to the narrowest point of the subject, the simple question 

 of the existence of caloric ; and that he nowhere gives evidence 

 of having the slightest notion of the quantitative relation between 

 mechanical force and heat, the futility of the claim which would 

 make him the experimental founder of the dynamical theory, is 

 abundantly apparent. 



The inquiries opened by Rumford and Davy were not formally 

 pursued by the succeeding generation. Even the powerful adhe- 

 sion of Dr. Thomas Young perhaps the greatest mind in science 



