viii THE HUMAN RACES 351 



lungs, which mitigates the excessive heat of the environment in the 

 inhabitants of hot climates,, and the wearing of clothes and furs 

 by the natives of cold climates in order to lessen the loss of heat. 



Whereas life. in hot climates, says Ranke, is so arranged as 

 to facilitate as much as possible the emission of heat from the 

 surface of the body by means of absence or lightness of clothing, 

 free ventilation, and cold baths, the natives of cold countries 

 protect themselves against loss of heat by every means in their 

 power. 



Ranke, basing his remarks on the result of his own research 

 work and on the information afforded him by explorers conversant 

 with the alimentation of different races, points out the error of 

 the statement so often made that the exchange of material, or, to 

 put it better, the general need of oxidation in people living in 

 hot climates, is much less than in people inhabiting cold or 

 temperate climates. It seems to me, however, that the investiga- 

 tions which have hitherto been made tend to show that a 

 difference, albeit a small one, does exist. 



With reference to the inhabitants of hot climates we will 

 take the results of the examination made by Glogner in 1889 

 of European soldiers who had lived for some time in the tropical 

 climate of Sumatra. He found a smaller consumption of protein 

 in those Europeans who had lived for any length of time in that 

 country and might therefore be considered acclimatised. Soldiers 

 who had spent less than four years there eliminated on an average 

 0143 grm. of nitrogen for every kilogramme of body-weight, 

 against O'lOl grm. in the case of those who had been there more 

 than four years, a figure closely approaching that observed by 

 Chittenden in economic proteid nutrition (page 97 and following 

 pages of this volume). 



Lehmann, on the contrary, found that the quantity of 

 sodium chloride eliminated in the urine of the individuals 

 examined by Glogner was the same as in Europe that is, on an 

 average 15'65 grms. in twenty-four hours. 



In 1889 Glogner began his first calorimetrical examinations 

 of twenty European and twenty Malay soldiers with the object of 

 establishing the amount of heat lost by the skin of the forearm. 

 For this purpose he made use of a water-calorimeter. He 

 found that the dark skin of the Malays emitted heat more 

 easily than the fair skin of the European, since the Malay skin 

 lost 1O5 units of heat to the square centimetre in half an hour 

 and the European skin only 8*7. Glogner calculated that a 

 European, having a bodily superficies of 15,000 square centimetres, 

 would yield 6,255,000 units of heat to water at 28 C. in which 

 he was immersed, supposing, that is, the same capacity for 

 emission to exist all over the body, as against 7,560,000 units 

 yielded by a Malay (a difference of 1,305,000). 



