HILL SANITARIA. 69 



in the absence of considerably stronger evidence we 

 should hesitate to receive them as conclusive, for a 

 number of reasons, which it would be too long to go 

 into at present especially as it is notorious that false 

 alarms have from time to time been raised about sup- 

 posed outbreaks of yellow fewer, which have after- 

 wards turned out to be typhus, or some other form of 

 outward febrile affections. 



In the West Indies we may point to the hill stations 

 of Jamaica and San Domingo, which have thus far 

 proved to be exempt from this scourge. Another 

 instance is met with in Brazil, near Rio Janeiro, itself 

 a hot and unhealthy place at certain seasons, with 

 defective sanitary arrangements, from which a short 

 journey, in like manner, takes the traveller through 

 lovely scenery to Petropolis, which at an elevation of 

 some 2400 feet above sea-level, has thus far also 

 proved exempt from epidemics of this disease. Similar 

 cases might be multiplied but we pass on to the 

 consideration of another important factor in climate, 

 namely, the effect of moisture in the form of atmo- 

 spheric vapour. According to the Encyclopeedia Bri- 

 tannica, " Climate is practically determined by the 

 temperature and moisture of the air, and those in their 

 turn are dependent on the prevailing winds, which 

 are charged with the temperature and moisture of the 

 regions they have traversed." * 



But these conditions are constantly modified, as we 

 have already pointed out, by the elevation of the land 

 above sea-level. It is, however, only when we come 

 to contrast the effects of a dry with those of a humid 



* Encycl. Brit. 9th edit. Vol. xvi, 1883, p. 114. 



