An Account of some Experiments on Animal Heat, 451 



occasional destroying force. It is my humble task to point out 

 a fact, as a contribution to that mass of accnmulating informa- 

 tion on which a consolidated fabric may at some future time be 

 erected. Yet the idle spectator or enthusiastic lover of Nature, 

 vvho shall hereafter view this interesting spot, may, when he 

 <^ontemplates these grand revolutions, learn to wonder less at 

 the efforts of that jjower which has hollowed the cave of Fingal^ 

 and submerged in the depths of the ocean those columns which 

 seemed destined for eternity. 



LXXII. An Arcmint of some Experiments on Animal Heat. 

 By John Davy, M.D. F.R.S* 



J- HE recent inquiries of Mr. Brodie have rendered questionable 

 the different prevailing hvpotheses relative to animal heat, and 

 have s!)own that fresh investigation is necessary, before we can 

 expect to arrive at any accurate theory. 



In the present uncertain state of our knowledge^ three cir- 

 cumstances are particularly deserving of attention, viz. the rela- 

 tive capacities of venous and arterial blood for heat, their com- 

 parative temperatures, and the temperatures of different parts of 

 the animal tjody. 



On the first of these subjects we possess only the experiments 

 of Dr. Crawford, which I believe ha.ve not vet been repeated, 

 notwithstanding they form the basis of his hypothesis. 



On the second, little inquiry has been made, and especially of 

 late years, since the improvement of the tliermometer. 



And on the third, the observations that have been collected are 

 very few in number, and, with the exception of those of Messrs. 

 Hunter and Carlisle, are scarcely, perhaps, deserving of confi- 

 dence. 



Such W'Cre the inducements tliat led me to the consideration 

 of each of these subjects apart, and to endeavour to acquire by 

 experiment some more certain knowledge respecting them. The 

 experiments that I have made will be described in the two fol- 

 lowing sections, and in the last will be offered the few remarks 

 and conclusions v.hich naturally arise, and are fairly deducible 

 from the results. 



1. On tfie Capacities of venous and arterial Blond for Heat. 

 I must premise, that my object has been to endeavour to ascer- 

 tain the relative capacities of venous and arterial blood for heat, 

 rather than their exact specific caloric. The latter, from many 



* From the Pliilosophical Traiisactious for 1814, part ii. 



F f 2 circum- 



