782 INFLUENCE OF CLIMATE ON THE 



the whole at Calcutta, at Chinsurah ^, and 

 at Berhampore ^. In north Africa, the mor- 

 tality from phthisis is still less, according to M. 

 Guy on, a medical officer of the French army, who 

 states that from 1838 to 1841, it was only ^ of the 

 whole among the Moors at Algiers, among the 

 Jews, r, and about -^ among Europeans. 



But why is it, that the mortality from diseases 

 of the lungs is so much greater among negroes of 

 the West Indies, than among Europeans? And 

 why are the latter so much more liable to fevers 

 when removed to tropical climates, than the na- 

 tives? The solution of these queries must be 

 sought in the radical difference of organization 

 of men and other animals in cold or temperate, 

 and in hot climates. For example, we have seen 

 that owing to the high temperature of tropical 

 Africa, for the greater part of the year, during 

 the heat of the day, respiration is proportionally 

 diminished, and the lungs exercised less, than in 

 colder climates, by which the size of the thorax 

 is accommodated to the wants of the system ; so 

 that when removed to the West Indies, where the 

 maximum temperature is from 10 to 20 lower, 

 the natives of Africa are unable to obtain caloric 

 from the atmosphere by respiration, as fast as it 

 is abstracted by the surrounding media, especially 

 in the high lands, or during the prevalence of 

 northerly winds, and early in the morning when 

 the air is damp. 



