560 ANNUAL REPORT SMITHSONIAN INSTITUTION, 193 



generation to generation, but the climate of this elevated region is 

 very different from that of the hot and moist latitudes along the 

 equator. Yet tropical mountains and plateaus lack one feature of 

 essential importance. They ma}', perhaps rightly, be said to have a 

 " perpetual spring," but they lack distinct seasonal variety. They 

 lack the tonic of a cold winter. Their temperatures are, it is true, 

 lower than those nearer sea level, but although the temperature scale 

 is lower, the same monotonous succession of notes is played upon it. 

 They are temperate in the sense of having tempered heat. They are 

 not " temperate " in the sense that they have temperate zone charac- 

 teristics of distinct seasonal variety; of constantly fluctuating 

 weather changes ; of the alternation from warmer to colder winds, 

 and from storm to fine weather. Tropical mountains and plateaus 

 have monotony ; a monotonous repetition of the same weather. That 

 is the secret of their failure in solving the problem of acclimatiza- 

 tion. They do offer immunity from certain tropical diseases. They 

 fail to provide the " spur of the seasons " to which we are accus- 

 tomed in temperate latitudes. The nonseasonal character of tropical 

 climates — the so-called " perpetual spring " — is not by any means the 

 best fitted for man's mental or physical development, however pleas- 

 ant it may be for a time. Many tropical hill and plateau stations 

 are beneficial in restoring those exhausted by overwork or by the 

 heat of the lowlands. They are especially advantageous in the cases 

 of white women and children. Nevertheless, climates temperate 

 because of altitude can not replace climates " temperate " because of 

 latitude. 



In the problems of acclimatization and colonization in the Tropics 

 cur concern is chiefly, although not by any means solely, with the hot, 

 damp, and rainy climates found generally in the latitudes near the 

 Equator: The climates of the Amazon and Congo forests, for ex- 

 ample ; of the west coast of Africa and of northern South America ; 

 of the typical tropical jungles ; of the steamy oppressive "hot-house" 

 type. It is in these more or less constantly wet climates that we 

 find the wealth of tropical products which chiefly attracts the white 

 man. It is here that, on the whole, there are the greatest possibilities 

 for future food supply. The economic return is mainly from the 

 damp lowlands, and not from the deserts or from the high plateaus 

 and mountains. It is fairly safe to say that it is specifically the 

 rainy low-latitude type of climate which promises the greatest po- 

 tential agricultural resources, and also presents tlie most serious 

 handicap to white settlement. It is with this climate that the prob- 

 lem of acclimatization is mainly concerned. 



In the minds of most people the acclimatization problem is merely 

 a question of whether a single white man or woman can live for a 

 time in a tropical climate in reasonable comfort and with a fair 



