MAN AS A HOMOIOTHERMIC ANIMAL 99 



tween blacks and whites (Woodruff, 1916). In compar- 

 able areas of skin the former have more sweat glands 

 than the latter. The basal metabolism of the white 

 natives in tropical Brazil was found by Almeida (1919, 

 1920) to be 24 per cent low^er than in the inhabitants of 

 temperate zones. ** Their habitual intensity of heat pro- 

 duction is a factor additional to the law (Rubner-Eictet) 

 of surface area, and its lowering is regarded as an adap- 

 tation to their environment, and an advantage in their 

 struggle against high air temperatures." The same 

 holds true for the colored inhabitants of Brazil. On the 

 other hand Eijkman (1921) found in the Dutch East In- 

 dies that the basal metabolism of blacks and whites was 

 about the same as of those in temperate climates. In 

 reviewing these papers Halliburton notes that white men 

 in warm dry climates usually have a high color and profit 

 by exercise, while those in warm moist climates are 

 often pale and take little exercise. There is need for 

 more knowledge concerning the effects of tropical cli- 

 mates on the various races of men. 



Life Indoors. — As civilization progresses man has less 

 contact with pioneer conditions of life ; his environment 

 and his daily, annual, and perennial life become more 

 and more monotonous. He must therefore take thought 

 for the morrow and, while insuring stability in his liv- 

 ing, also retain the variety which is the spice and leaven 

 of life. A dwelling should not furnish such an artificial 

 environment that it is monotonous or abnormal. Colds 

 are incubated in steam-heated houses where there is in- 

 sufficient moisture. Tuberculosis flourishes among those 

 who live indoors in dust and darkness. The great mass 

 of the Chinese people is docile, unprogressive, hopeless, 

 and stolid largely on account of monotony — sameness 

 in diet, social contacts, and outlook for the future. Man 



