570 MAN'S ADAPTATION TO CLIMATE. 



blue. Their complexion is sometimes of a yellowish-white, as with 

 the Laplanders ; sometimes of a deep yellow or reddish-brown, as 

 with the Eskimos and the Greenlanders. The latter peculiarity may 

 be invoked as a very plausible argument in support of the opinion 

 which gives to the Arctic peoples different origins. It shows also, 

 once more, that the more or less intense colouring of the skin among 

 the African races is not an effect of the solar heat, as was commonly 

 supposed. 



Considered from a physiological point of view, the Hyperboreans 

 are distinguished by a remarkable uniformity of characteristics, which 

 deserve to be specified. The sanguine temperament predominates 

 among them. Their nervous system is but slightly developed, their 

 sensibility blunted, their intelligence slow, their imagination feeble. 

 Their external perspiration is almost null, and they are accustomed 

 to suppress it entirely by induing their bodies in oily substances. 

 On the other hand, their organs of nutrition and respiration are 

 endowed with an extraordinary activity ; and in this lies the secret 

 of the extreme facility with which they support for several successive 

 months the most rigorous cold. We know, indeed, that man and the 

 warm-blooded animals possess, in their respiratory apparatus, a posi- 

 tive internal furnace, where a notable part of the carbon and the 

 hydrogen contained in their venous blood is consumed in contact 

 with the air. But to maintain this furnace at such a degree of heat 

 as shall always preserve the temperature of the body at its normal 

 standard (39 C.), the inhabitants of Arctic climes need constantly 

 feed it with fuel, that is, with substances rich in carbon and hydrogen. 

 Hence the keen appetite of the Hyperboreans for oil, fat, and flesh ; 

 hence, too, their voracity. The inhabitants of torrid or temperate 

 regions, while sojourning among the icy wastes of the Pole, quickly 

 become sensible of the same necessity, and eagerly feed upon aliments 

 which elsewhere would inspire them with insurmountable disgust. 



It is a remarkable fact that most of the diseases so frequent and 

 so murderous in civilized countries are unknown in the Polar lands. 

 But, on the other hand, ophthalmia" is endemic, and the cutaneous 



