WATER AND RAIN. 1 1 ." 



lr.il ul' th" supply of local evaporation, which is the 



: tl element iii tin- amount of rain fall." 

 \\'" admit that drainage lessens tin- rain fall, net for his 



>. lnii Inrause there i* less concentrated activity in vege- 



-iM\vth, and consequently a smaller supply of vegetable 

 exhalations necessary for forming rain. Still we would not say 

 that drainage is had, for a clump of trees at the end of a field, 

 would counteract the effect of drainage over a hundred acres. 



These facts regarding vegetable exhalations, give us an 

 insight into the cause of fever and malaria. A hundred years 

 ago the sites of many of those great western cities in America 

 St. Louis, Chicago, Cincinnati, and others, were fever swamps, 

 full of all kinds of malaria, striking down the strongest man 

 that took up his abode in their midst ; yet they are now as 

 healthy as any of the cities of the Republic. Why were these 

 cities unhealthy? Becau.se there was too much vegetation 

 present with decomposing vegetable matter, and in consequence 

 more oxygen or vegetable gas in the atmosphere, than is suitable 

 for the health of man. We never hear of a city being a place 

 of fever and ague, especially one which is largely built of brick 

 and stone, unless the drainage and cleanliness are defective, 

 fur the vegetable emanations in its area are very scant. 

 But allow the cities to go to ruin, let them be overrun with 

 vegetation, as in the case of Palenque and Uxmal in Central 

 America, or those magnificent ruined cities of Cambodia in 

 Siam ; and they become as dangerous to the life of man, as the 

 worst ague swamps known. 



A curious fallacy expounded regarding water, is, that it con- 

 tains a quantity of air. Prof. Tyndall proves this by saying 

 that bubbles rise to the surf a .vattr is boiled. But if 



