542 POPULAR SCIENCE MONTHLY. 



find vigorous descendants to the third and fourth generations. There 

 are many such families in Porto Kico, and the same is true in the Sand- 

 wich Islands. 



It is here maintained that it is the letting go, little by little, the 

 correct views of living, which causes the white race to deteriorate, and 

 not the climate. The necessities of life are fewer and easier to obtain 

 in hot countries than in cold ones; and this makes it easy for men to 

 become indolent, to lose ambition and to sink to a low level of living 

 and thinking. 



The Tropics, contrary to the usual view, are healthful regions. 

 Malaria exists in hot countries, but so it does in temperate ones. Ty- 

 phoid fever and contagious diseases are no worse than in cold climes. 

 Smallpox is regarded as a mild disease. Scarlet fever is said not to 

 exist at all. Where filth is allowed to accumulate disease prevails, but 

 in lands well drained and free from decaying matter and filth, there is, 

 under ordinary care, no more to be feared from disease than in the most 

 favored portions of the earth. At present, in hot countries the people 

 pay little attention to sanitation. As a rule, they are unutterably dirty. 

 They live in their own filth, and seem to enjoy it. The germs of disease 

 from one body are promptly taken into another before they have time 

 to die, or are cultivated in filth deposits until the whole community is 

 affected. 



The Tropics, in themselves, are no more and no less healthful than 

 temperate regions. But the people in cold countries have some respect 

 for sanitation, while those in hot countries have very little or no respect 

 for decent cleanliness. This is the whole explanation of this matter. 

 People who have the latrine in the kitchen and uncleaned for a century, 

 who sleep in rooms into which a breath of fresh air cannot enter; who 

 seldom wash their bodies; who use rum and tobacco instead of food; 

 who permit children to cohabit promiscuously, can scarcely hope to 

 escape disease, if any prevails in their neighborhood. Such conditions 

 are the rule with the masses in hot countries. 



Those who become 'acclimatized' will be able to live in hot coun- 

 tries. It is doubtful whether or not there is any actual condition 

 known as 'acclimatization,' although if the term means becoming ac- 

 customed to filth, and to certain germs which live in filth, there may 

 be something in the term. 



Instead of a bodily change, the individual gradually becomes edu- 

 cated to his new environment. He learns what to eat and drink, what 

 to wear and where to sleep, when and how much to work, to come in 

 out of the shower and to change his wet clothes, to avoid the midday 

 sun and the damp air of the night. When a man new to the Tropics 

 has learned these things, he is 'acclimatized.' Some learn them at 



