CLIMATE AND HEALTH. 313 



except by supposing our earth solid (or very thick in crust), cool- 

 ing and contracting unequally. 



As to other arguments for the fluidity of the earth, we have 

 seen that volcanic phenomena carefully studied go against the 

 idea of one central reservoir for the lavas. It is, of course, natu- 

 ral to think of a cooling globe as having a solid crust and molten 

 interior, but it is quite possible that solidification started at the 

 center, just as even now in the nebulous stars the condensation 

 from gaseous to liquid state proceeds from central points or 

 nuclei. 



We may say, then, in summing up, that there are no valid 

 arguments against the conclusion to which all the facts point, 

 that the earth is at heart an intensely hot but practically solid 

 mass of iron. 







CLIMATE AND HEALTH.* 



By Dr. CHARLES FAYETTE TAYLOR. 



IN the divisions of land and water, the situations of the conti- 

 nents, the seas, and the islands in the seas; the mountain 

 ranges and the rivers which have their sources in them ; the ele- 

 vations and depressions of the more even surfaces, together with 

 procession of the seasons and the earth's diurnal revolutions, we 

 have some of the conditions for a great variety of climates. Pro- 

 ceeding from the equator toward the poles or moving along the 

 surface of the earth in any direction, man, who seems to be the 

 toughest animal on the face of the earth, can so adjust himself 

 to varying climatic conditions as to exist in fairly good health 

 almost anywhere, from the steaming equatorial jungles to the 

 regions of perpetual ice and snow, as well as in intermediate 

 locations where often heat and cold vary from one extreme to the 

 other in rapid succession. And yet men live and thrive in nearly 

 all lands and under the most diverse conditions, and with intelli- 

 gent self-adjustment to their environment they may live well and 

 live out their allotted times as a general rule. While the human 

 race is exceedingly flexible, and can adapt itself rapidly to very 

 diverse conditions, such adaptations, be they rapid or relatively 

 slow, are not accomplished without an expenditure of energy to 

 correspond with the functional modifications thus brought about. 

 We call the process acclimatization, and the person, after subjec- 

 tion to the process, we say is acclimatized. That is to say, the 

 functional activities of such a person have become adjusted to his 

 environment ; his functions have learned to harmonize with the 



* Read before the New York Academy of Medicine, October 4, 1894. 

 vol. xltii. 26 



