PHYSICAL AND LITERARY 99 



And thus in the afcent of vapour from 

 boiling water, we have difcovered another 

 caufe of evaporation, viz. a mutual repul- 

 fion among the particles of water. This 

 power, by expanding the water fo as to 

 make it 17 times lighrer than air, makes 

 it, in the iliape of vapour, afcend into 

 the air; and tho' it be there foon again 

 condenfed by the cold of the air, yec it 

 is kept fufpended by the mutual attrac- 

 tion between air and water. 



Neither of thefe caufes will account 

 for the evaporation • of water in vacuo. 

 Ele(5live attraclioa will not anfwer when 

 there is no incumbent air to attract 

 the water. Nor will mutual repuliion 

 anfwer; becaufe, in evaporation in va- 

 cuoj there is not fuppofed to be any 

 extraordinary heat. The beft way to ac- 

 count for this fuppofed evaporation, at 

 leafl the eafieft, is to deny the fad, which 

 may be done bona Jick, for I have noc 

 heard of any experiment that verifies ic. 

 I fhall venture only a fingle hint, that an 

 eledive attradion betwixt glafs and w^-- 

 ter, fuppofmg the fadl to be afcertained, 

 will fairly account for the phenomenon. 



Art, 



