SECT. II.] ANIMAL HEAT. 109 



of acclimatization, a lesser destruction of life by diseases, and 

 greater muscular strength, is found among civilized nations, 

 owing to their protecting themselves from injurious influences 

 of all kinds, in combination with superior nutrition and regular 

 exercise. 



The mean animal heat and the frequency of respiration do 

 not materially differ under the tropics and the polar regions. 

 Some indeed have maintained that the first is in the torrid 

 zone less by 2 3 ; others (Davy) that in Ceylon it is higher 

 by 2 ; this however has not been confirmed. Grmelin, Ross, 

 and Parry found under 74 N. lat. no difference in this re- 

 spect. 1 That Livingstone 2 found the thermometer under his 

 own tongue rise to 100, and among the natives only 98, 

 affords no certain proof of a constant difference between the 

 blood heat of the Negro and the European. The difference 

 may have been the sequel of his fever or the effect of other 

 circumstances. Nor has the pretended quicker pulse of the 

 Southerns been confirmed. Among some North American 

 tribes the pulse is only 64, which is perhaps connected with 

 the rarity of fevers among them. 3 Prichard 4 refers this cir- 

 cumstance to a deficient energy of the animal functions, since 

 also the menstruation of the women among many Indian 

 peoples is said to be but scanty, 5 and puberty of the girls 

 occurs later, from the eighteenth to the twentieth year, the 

 capacity to produce children ceasing with the fortieth year. 

 These phenomena are however far from common among the 

 American race, for the period of puberty among girls com- 

 mences in the fourteenth year among the Potowatomis, in the 

 fifteenth and sixteenth among the Sioux. 6 Among the Dela- 

 wares and Iroquois the girls marry at fourteen, 7 and in the 

 torrid zone, marriages are earlier effected among the natives of 



1 Foissac, p. 15. 



2 Loc. cit., p. 166. 



8 Say in James, loc. cit., p. 260. 



4 Chap, i, p. 133. 



5 Lahontan, " Nouv. voy. dans 1'Am. sept.," ii, p. 154, La Haye, 1703 ; and 

 Rengger, "Natgesch. der Saugeth v. Paraguay," p. 11. 



6 Keating, "Narr. of an exped. to the source of St. Peter's E.,"i, p. 434, 1825. 



7 Loskiel, " Gesch. d. Miss, unter den Ind./' p. 72. 



