o/ the Vital and Physical Forces. 373 



then stated that he had been led by these and other facts, in 

 conformity with the great discovery by Professor Faraday of the 

 analogy of light with magnetism and electricity, to consider light 

 as the primary source of all vital and instinctive power, the de- 

 grees and variations of which, he suggested, may, perhaps, be 

 referred to modifications of this influence on the special organi- 

 zation of each animal body. The close relation which Mr. Fa- 

 raday has now shown to subsist between light and electricity, 

 and by Matteucci between electricity and nervous power, and the 

 known dependence of most of the functions of the body on the 

 latter, were remarked on as leadmg to the above conclusion/' 



A further report of the same views, but somewhat more de- 

 tailed, was afterwards published in the ' Proceedings ' of the Lin- 

 nsean Society (vol. i. p. 271), and in the 'Annals and Magazine 

 of Natural History' for May 1846 (vol. xvii. p. 352). 



Thus the connexion of the vital and physical forces through 

 liffhtj heat, electricity and nervous function was pointed out by 

 myself in November 1845. 



The masterly views by Mr. Grove respecting the correlation of 

 the physical forces had then already been published in a report 

 of his Lectures in the Literary Gazette for January 1844, but 

 with them I was entirely unacquainted. No allusion however is 

 made in that report to the vital forces, or to any connexion of 

 these with the physical. Mr. Grove afterwards published a sum- 

 mary of his views in a separate form in August 184^, and it is 

 interesting to find near the end of his essay the following pas- 

 sage : — 



" I believe that the same mode of reasoning as I have adopted 

 in this essay might be applied to the organic as well as to the 

 inorganic world, and that muscular force, animal and vegetable 

 heat, &c., might, and at some time will be shown to have similar 

 definite correlations ; but 1 purposely avoided the subject as per- 

 taining to a department of science to which I have not devoted 

 my attention.'' 



Thus the idea of a close relation between the vital and phy- 

 sical forces by myself in 1845, and of a correlation of the vital 

 forces by Mr. Grove in 1846, precede the remarks in the ' British 

 and Foreign Medico-Chirurgical Review ' for January 1848, and 

 also Dr. Fowler's communication to the British Association in 

 September 1849. 



But what until lately has been merely a view or idea, or at most 

 an imperfect theory deduced from a comparison of well-known cir- 

 cumstances, is now, in some respects, confirmed by experimental 

 facts recently communicated by Matteucci to the Royal Society 

 and printed in the ' Transactions ' (Part 1. 1850). In that com- 

 munication electricity is shown by direct experiment to develope 



