4:06 



term, 1 and in cases of persistence of the foramen ovale. In 

 certain instances in which life has been prolonged under this 

 abnormal condition, the individual is nearly in the condition 

 of a cold-blooded animal. We can also understand the re- 

 markable power of resistance to asphyxia in newly-born 

 animals observed by Buffon, Legallois, and Edwards ; a for 

 it is well known that cold-blooded animals will bear de- 

 privation of oxygen much better than the higher classes. 



In adult life there does not appear to be any marked and 

 constant variation in the normal temperature; but in old 

 age, according to the observations of Davy, while the ac- 

 tual temperature of the body is not notably reduced, the 

 power of resisting refrigerating influences is diminished 

 very considerably. 3 



There are no positive observations showing any constant 

 differences in the temperature of the body in the sexes ; and 

 it may be assumed that in the female, the animal heat is 

 modified by the same influences and in the same way as in 

 the male. 



Diurnal Variations in the Temperature of the Body. 

 Although the limits of variation in the animal temperature 

 are not very extended, certain fluctuations are observed, de- 

 pending upon repose or activity, digestion, sleep, etc., which 

 it is necessary to take into account. These conditions, which 

 are of a perfectly normal character, may produce changes in 

 the temperature amounting to from one to three degrees. It 

 has been ascertained that there are two well-marked periods 

 iii the day when the heat is at its maximum. These, according 

 to the most recent observations in Germany, are at eleven 

 A. M. and four p. M. ; and it is a curious fact, that while all 



1 W. F. Edwards noted a temperature in the axilla, of a little loss than 90, 

 two or three hours after birth, in an infant born at the seventh month ( Op. tit., 

 p. 236). 



2 See vol. i., Respiration, p. 420, et seq. 



3 DAVY, On the Temperature of Man in advanced Age. Physiological Re- 

 searches, London, 1863, p. 4, et seq. 



