EVAPORATION, &C. 17 



exposed, and the consequent impoverishment which 

 ensues, more than counterbalances the extra profit 

 which he deiives. It should be enough that he de- 

 rives the benefit of a crop from every field. The 

 four crops of clover will be as profitable as the two 

 crops of grain, after deducting the expenses of culti- 

 vating the latter Evaporation is the great enemy to 

 land ; a much greater enemy than mankind have yet 

 conceived it to be. That the system advanced in this 

 book may be the better understood, I shall describe 

 the manner in which water is taken up into the high- 

 er regions; how clouds are formed, and the rain 

 thrown down upon the earth. 



PHILOSOPHICAL EXPOSITION OF EVAPORATION 



OP THE ASCENT OF VAPOUR OF THE FORMATION OF 



CLOUDS AND OF THE CONDENSATION AND FALL OF 



RAIN. 



IT is a fact well known in Natural Philosophy, 

 that all the water of the earth, seas, lakes, rivers, &c. 

 is alternately raised by the heat of the sun, and 

 thrown down from the clouds to the earth. This 

 beautiful process, this wise provision of nature, is 

 constantly going @n day and night, Winter and Sum- 

 mer. It is from this cause that the earth is not drown- 

 ed by the vast quantities of water which fall upon 

 it. It is a well known truth, that there is not one 



