I9I3-] HIGHEST NATIVE AMERICAN CIVILIZATION. 477 



The plagues of the Middle Ages loom large in history, but they did 

 not do a tithe as much harm as syphilis. Yellow and typhus 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 populations, not killing them, not even doing 

 more than spoil their work 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 we, in our huge folly, long neglected 

 consumption and still largely neglect the even more insidious ordi- 

 nary 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 weakened 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, one of the chief 

 authorities on the subject, has to say: 



" These diseases do no affect only immigrant Europeans, they are ahnost 

 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 afifects every one of 

 the children, probably kills a large proportion of the newborn infants, and 

 renders the survivors ill for years. Here in Europe nearly all our children 

 sufifer from certain diseases — measles, scarlatina, and so on. But these 

 maladies are short and slight compared with the enduring infection of malaria. 

 When I was studying malaria in Greece in 1906 I was struck with the impos- 



