8CIKNCK AND MAN ;! 



the ocean from which it nine. Up to the point where 

 condensation begins, an aimun '{divalent 



to the molecular work of \ 'id tin- \\ 



work of lifting the vapor .untain top, ha> 



1 from the universe. Wh.. spmiiiin^ 



to tli is los leased 



in a foreign currency. Tin- !<>s i< a loss of heat; th- 

 is a gain of distant \atet and : 

 Water which WHS formerly at tin- sea- level i lifted 

 to a position from which it can fall: N-s wliirh l.a\e 

 been locked together as a liquid an- now separate i as ?apor 

 which can ivcon dense. After <: .i-nsation gravity comes 

 into effectual play, pulling the showers down upon the 

 hills, and the ri\n-> thus cn-atctl through their gorges to 

 the sea. Every raindrop which snni.-s the monnUii 

 duces its definite amount of heat; every rifer in it> 

 develops heat by the clash of its cataracts and tl-e friction 

 of its bed. In the act of condensation, moreover, the 

 molecular work of vaporization is accurately reversed. 

 Compare, then, the primitive loss of solar warmth with 

 the heat generated by the condensation of the vapor, ami 

 by the subsequent full of the water from cloud to sea. 

 They are mathematically emial to each other. No v. 

 of vapor was formed and lifted without being paitl for in 

 the currency of solar heat; no particle returns as water to 

 the sea without the exact quantit.i itntion of that 

 heat. There is nothing gratuitous in physi. d nature, no 

 expenditure without equivalent gain, no gain without 

 equivalent expenditure. With inexorable constancy the 

 MM accompanies the other, leauni: no nook or c: 

 between them for spontaneity to mingle with the pu: 

 necessary play of natural force, lias this uniform 

 nature ever been hmken;' The reply is: "N 



ledge of sciei 



What has been here stated regnrdini; heat and gt 

 applies to the whole of inorganic nature* Let us ta 



illustration from dii-in tal y.inc may he! 



in oxyeci -nut of heat being pro- 



Hut /.in. , \ M Inn-; 



supply of in water, for example. It do,-> not in 



this case , pr.du. 



ible of ;K hut th. 



