122 THE LAWS OF ORGANIC 



system by such an operation ; and I shall now 

 endeavour to show, that one great error which 

 pervades the work of Dr EDWARDS, concerning 

 animal temperature, is referrible to a similar 

 cause. This gentleman states, that the faculty 

 of producing heat is invariably less in young ani- 

 mals than in adults; and the chief proof which he 

 gives is, that if young and old animals be exposed 

 to the same degree of cold, the temperature of the 

 former almost immediately falls, and continues to 

 do so unless they be removed to a warmer medium, 

 while that of the latter is little if at all affect- 

 ed by the refrigerating influence. This constant 

 result made him conclude, that young animals 

 do not generate an equal quantity of heat, be- 

 cause he supposes, if this were the case, they 

 would both bear with the same facility the ex- 

 posure to cold. From the development of other 

 views, it will be , clear, that they may generate 

 the same proportionate quantity of heat, and yet 

 may be unable to bear the same extent of cold. 



CXXX. Dr EDWARDS took the temperature 

 of 20 adults, and found the medium to be 36. 12 

 centigrade thermometer; and from 10 infants 

 whose temperature was taken in the same way, 

 the medium was found to be 34. 7. In these ex- 

 periments the thermometer was placed in the arm- 

 pit. There are many objections to this mode of 

 ascertaining the degree of animal heat. The part 

 is particularly subject to perspiration, which may 

 modify very much the results ; or if the arm has 



