Chap, i.] Incompre/tble an J Elaftic Fluids. 381 



which takes place in twelve hours to be that above 

 mentioned, without having any regard to what is 

 evaporated from the whole of the land, or from 

 the Tea during the other twelve hours, it will be 

 found that the atmofphere has taken up no lefs than 

 20,302,535,177,834, or more than twenty millions 

 of millions of cubic feet ef water ; an enormous quan- 

 tity, and much more than fufficient to fupply all the 

 fivers that interfecT: the different quarters of the 

 globe*. 



What particularly diftinguifhes water, and thofe 

 fluids which are of a iimilar confiftence, and in com- 

 mon language are termed liquids, from thofe fubtile 

 fluids which were treated of at large in the preceding 

 volume, is, that the former are not, like the others, 

 pofTdTed of that lurprizing elafticky which admirs of 

 the volume of fluid being condenfed into a fmall com- 

 pals i but, on the contrary, may be confidered as incapa- 

 ble of compreffion, or at lead are compreffible in a very 

 Highc degree. The Florentine academicians filled a 

 globe of gold with water, and comprefled it with im- 

 menfe force ; the firft effect of this comprefflon was, 

 that the ball was confiderably heated by the emiflion 

 of latent heat from the water, and afterwards the fluid 

 forced its way through the pores of the gold, or 



* There will poflibly be apparent, in this part of the work, 

 fome degree of repetition \\hen cornp^ed with what was faid of 

 vapour in the firft book. It was then neceffary to fpeak of va- 

 pour, in explanation of the properties of heat ; i: is now neceffary 

 to treat of it in connection with tha fluid of which it is ufua!'y 

 .formed ; and I conceive it better to do this, with the rifk of fome 

 repetition, than to refer to a former volume, both becaufe it wilj 

 ferve more firmly to imprefs on the minds of young readers fome 

 of the moft important doclrines of philofophy : and becaufe what 

 may now appear as repetition, is, in this place, mixed with new 

 facts, which coujd not be previoufly introd'. 



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