INFLUENCE OF CLIMATE. 403 



with black hair and eyes ; but as we ascend towards the more 

 elevated districts these disappear, and in their stead come out the 

 fair skin, blue eyes and auburn hair. Traders from the gold coast 

 of Africa, inform us that natives come down to the sea from the 

 distant interior having a light complexion, hazel eyes and red hair, 

 though possessing all the features of the real Guinea negro. From 

 such information as can be gleaned from them, it is inferred that 

 they inhabit elevated districts far inland. 



At the two extremes of the western hemisphere are found the 

 light-tinted representatives of the human family, but as we ap- 

 proach the equator the tint deepens. Along the line of the Andes 

 there are special local illustrations of the same fact, the dwellers 

 on the elevated plateaux being lighter-hued than those inhabiting 

 the valleys, or on the same parallel nearer the Atlantic border. 

 In the Ijght of such facts, no one can, therefore, safely question 

 the conclusion that man, after a long residence in a locality having 

 a high temperature, will become dark-hued, but if subjected to the 

 climate iniluence of a low temperature for successive generations-, 

 his complexion will take on a lighter tint. It must also be con- 

 ceded that these changes are alone tracable to the workings of 

 the^ame influences which, in form, color and texture, alters the 

 leaves of the tree transplanted from the soil of New England to 

 the sands of Florida. The details by which this modification is 

 produced belong to physiological science, and cannot be crowded 

 into this brief page. 



Still again, should the question here arise. Why has not the 

 western hemisphere in its tropical climate produced the negro-type 

 of humanity ? the answer will be found briefly in the fact that in 

 the central portion of our hemisphere there is not sufficient topo- 

 graphical expansion for the indigenous production of the negro. 

 The negro zone in Central America is barely fifty miles wide, 

 while in Africa it is more than four thousand. 



Were the task as short as it would be easy, many facts could be 

 adduced to show that not only in this superficial manner, but in a 

 much more profound degree, the structure and constitution of man 

 are changed by the climate in which he makes his permanent 

 home. One of the greatest living thinkers* in England maintains 

 that the effects of the definite action of external physical condi- 

 tions are tracable even to the tissues and fibres of the animal 

 structure. If, then, it be remembered that with a modified physi- 



* Herbert Spencer. 



