220 THE CLIMATIC FACTOR AS ILLUSTRATED IN ARID AMERICA. 



history, but they did not do a tithe as much harm as syphilis has done. Yellow and typluis 

 fevers may decimate a population, but they are far preferable to the slow, irresistible 

 ravages of recurrent malarial fevers, which rarely seem to kill, but merely undermine the 

 constitution, leaving both mind and body inefficient. Tuberculosis, in our own land, 

 is so dreaded that we wage a crusade against it, but its dangers are probably far less than 

 those of the insidious colds which year after year attack fully half of our northern popu- 

 lations, not killing them, not even doing more than lessen their efficiency for a few days, 

 and yet in the aggregate causing an incalculable amount of damage and giving an opening for 

 a large part of our cases of consumption, diphtheria, deafness, and many other afflictions. 

 Just as in our huge folly we long neglected consumption, and still largely neglect the even 

 more insidious ordinary colds, so the man within the tropics often ignores malaria. Again 

 and again I have talked with people who said there was no fever in the particular place where 

 they lived or that they had not had fever, but before the next meal they took a dose of 

 quinine, and that same night, perhaps, they reeled with a touch of fever or shivered with a 

 chill. They called it "nothing," but even quinine did not prevent them from being weak- 

 ened by it. Few foreigners, especially children, can live long in the lowlands under ordinary 

 conditions without being affected. As for the natives, it is often stated that they become 

 immune to fevers, but here is what Sir Ronald Ross, of the Liverpool School of Tropical 

 Medicine, and one of the chief authorities on the subject, has to say: 



"These diseases do not affect only immigrant Europeans; they are almost equally disastrous 

 to the natives, and tend to keep down their numbers to such a low figure that the survivors can 

 subsist only in a barbaric state. To believe this one has to see a village in Africa or India full of 

 malaria, kala-azar, or sleeping sickness, or a town under the pestilence of cholera or plague. 

 Nothing has been more carefully studied of recent years than the existence of malaria amongst 

 indigenous populations. It often affects every one of the children, probably kills a large pro- 

 portion of the new-born infants, and renders the survivors ill for years. Here in Europe nearly 

 all our children suffer from certain diseases— measles, scarlatina, and so on. But these maladies 

 are short and sUght compared with the enduring infection of malaria. When I was studying 

 malaria in Greece in 1906 I was struck with the impossibility of conceiving that the people who 

 are now intensely inflicted with malaria could be like the ancient Greeks who did so much for 

 the world ; and I therefore suggested the hypothesis that malaria could only have entered Greece 

 at about the time of the great Persian wars— a hypothesis which has been very carefully studied 

 by Mr. W. H. S. Jones. One can scarcely imagine that the physically fine race and the mag- 

 nificent athletes figured in Greek sculpture could ever have spent a malarious and spleno-megalous 

 childhood. And conversely, it is difficult to imagine that many of the malarious natives in the 

 tropics will ever rise to any great height of civilization while that disease endures amongst them. 

 I am aware that Africa has produced some magnificent races, such as those of the Zulus and the 

 Masai, but I have heard that the countries inhabited by them are not nearly so disease-ridden 

 as many of the larger tracts. At all events, whatever may be the effect of a malarious childhood 

 upon the physique of adult life, its effects on the mental development must certainly be very bad, 

 while the disease always paralyzes the material prosperity of the country where it exists in an 

 intense form. 



"Consider now the effects of yellow fever, that great disease of tropical America. The Liver- 

 pool School sent four investigators to study it, and all these four were attacked within a short 

 time. One died, one was extremely ill, and two suffered severely. The same thing tended to 

 happen to all visitors in those countries. They were almost certain of being attacked by yellow 

 fever, and the chances of death were one to four. But malaria and yellow fever are only some of 

 the more important tropical diseases. Perhaps the greatest enemy of all is dysentery, which in 

 the old days massacred thousands of white men, and millions of natives in India, America, and 

 all hot countries, and rendered survivors ill for years. Malaria has always been the bane of 

 Africa and India; the Bilharzia parasite of Egypt; and we are acquainted with the ravages of 

 kala-azar and sleeping sickness. Apart from these more general or fatal maladies, life tends 

 to be rendered unhealthy by other parasites and by innumerable small maladies, such as dengue 



