[ *9I 1 



corruption is checked by the vita! 

 operation of the plants in the fum- 

 mer, and by the cold in the winter; 

 By this obfervation, we may per* 

 haps be induced to believe, that 

 thofe countries which are very hot 

 in the fummer, and are little or not 

 cultivated, as is a great part of 

 Hungary and the country round 

 about Rome, are not only expofed 

 to have their air contaminated by 

 the breathing of animals in it, and 

 by the corruption of many other 

 fubftances, but alfo by the corrup- 

 tion which the air itfelf is liable to 

 undergo during the heat of the 

 feafon ; and which mifchief can 

 chiefly be remedied by making a 

 fufricient quantity of vegetables 

 grow in them, principally trees* 

 Draining the marines, and prevent- 

 ing inundations by keeping the ri- 

 tj 2 vers 



