ANIMAL HEAT. 405 



ceptional, the body of the infant and of young mammalia 

 and birds, removed from the mother, presents a diminution 

 in temperature of from one to nearly four degrees. This 

 important fact was established by "W. F. Edwards, 1 who 

 made, also, a number of curious and instructive experiments 

 upon the power of young warm-blooded animals to resist 

 cold. In infancy the ability to resist cold is less than in 

 later years ; but after a few days the temperature of the 

 child nearly reaches the standard in the adult, and the 

 variations produced by external conditions are less consid- 

 erable. These facts have been fully confirmed by the re- 

 searches of Despretz, 3 Roger, 8 and others. 



The experiments of W. P. Edwards have an important 

 bearing upon our ideas of nutrition during the first periods 

 of extra-uterine life. He found that in certain animals, par- 

 ticularly dogs and cats, that are born with the eyes closed 

 and in which the foramen ovale remains open for a few days, 

 the temperature rapidly diminished when they were removed 

 from the body of the mother, and that they then become 

 reduced to a condition approximating that of cold-blooded 

 animals ; but after about fifteen days, this change in tem- 

 perature could not be effected. In dogs just born, the 

 temperature fell after three or four hours' separation from 

 the mother to a point but a few degrees above that of the 

 surrounding atmosphere.* The views advanced by Edwards 

 are fully illustrated in instances of premature birth, when 

 the animal heat is much more variable than in infants at 



1 W. F. EDWARDS, De V influence des agens physiques sur la vie, Paris, 1824, 

 p. 234. 



8 DESPRETZ, Recherches experimentales sur les causes de la chaleur animate. 

 Annales de chimie et de physique, Paris, 1824, tome xxvi., p. 338. Despretz 

 found the temperature in three infants, between one and two days old, only 

 95-1. 



3 ROGER, De la temperature chez les enfants d Vetat phyxiologique et patho- 

 logique. Archives generates de medecine, Paris, 1845, 4me serie, tome ix., 

 p. 264. 



4 Op. tit., p. 132, et seq. 



