STUDY I. 



47 



feds of that vaft flratum of frozen air which fur- 

 rounds our Globe, about a leagife above the fur- 

 face, and of which hardly any one of the pheno- 

 mena has hitherto been explained. 



I (hall, next, confider the effeds of Water: in 

 what manner heat evaporates, and cold fixes it; 

 it's different exiftences ; of volatility in the air, in 

 clouds, in dew, and in rain ; of fluidity on the 

 earth, in rivers, and in Seas ; of folidity at the 

 Poles, and on lofty mountains, in fnow and ice. 

 I (hall enquire, how the Seas, which are the great 

 refervoirs of this element, are diftributed, with re- 

 lation to the Sun ; how they receive from him, 

 through the mediation of the air, a part of their 

 movements ; in what manner they continually re- 

 new their waters, by means of the ice accumulated 

 at the Poles ; the annual or periodical fufion of 

 which, maintains their flux and reflux as con- 

 Itantly, as the fufion of the ices on the fummit of 

 high mountains renews and fupplies the waters of 

 great rivers. I fliall hence deduce the phenomena 

 of the Tides, of the Monfoons in the Indian 

 Ocean, and of the principal Currents of the vaft 

 watery Element. 



I (hall, afterwards, hazard my conjedures re- 

 fpefting the quantity of water which furrounds the 

 Earth, in the three liâtes of volatility, fluidity, 



and 



