598 The Andes and the Amazons. 



courses of this section, these affections are also to be en- 

 countered. Excessive dryness and excessive moisture both 

 seem to prevent the accession of the malaria. The inte- 

 rior wooded lowlands, through which the sun has not shone 

 for ages, are as free from malaria as the mountain-tops. 

 Besides this unsunned condition which prevents evapora- 

 tion being one cause of exemption, the heavy rains and 

 the flooding for several months, which carry off the decay- 

 ing material, and the washing-out of the surplus still-water 

 lagoons, must, probably, be noted as among the partial 

 causes of healthfulness. This decaying vegetable matter 

 clogged with mud is deposited in the main stream, where 

 it is hidden from the sun's power, and the air preserved 

 innocuous. 



However, in speaking of the freedom of the main Ama- 

 zons from fevers, one must exercise a little reserve now 

 and then, on account of the inability to get at the true 

 condition of things among a native population which prob- 

 ably suffers and dies without our knowing it, in the nooks 

 and corners of the Amazons, where the unsettled nature 

 of the country does not admit of a true estimate of facts 

 being obtained ; but for the larger populations in the vil- 

 lages, frequent talks among the oldest residents will elicit 

 approximate truth. During the early part of the present 

 year, for instance, there was quite an outbreak of " fever " 

 among the natives on the low countries near the mouth 

 of the Amazons, some fifty or two hundred miles above 

 Para ; and so grave was it, that it attracted the notice of 

 the Para press, which was petitioning the government to 

 have medical aid sent to relieve the poor creatures. And 



ing apparently contradictory statements: "First, that the intermittent fevers 

 are severer in the region of the rapids than above or below them, where there 

 are still more fens ; second, that in the prairies of Bolivia, where, after the 

 floods, there is much stagnant water, which is drunk without much precau- 

 tion, the fevers are comparatively rare." — 0.] 



