212 CAUSE OF CHEMICAL ATTRACTION. 



It is therefore obvious, that if the earth could be 

 wholly deprived of solar heat, all its chemical mo- 

 tions and changes would cease. It was admitted 

 by Dr. Black, that " heat is indispensable to che- 

 mical action, by overcoming the cohesion of bodies, 

 and thus enabling them to exert their attractive 

 powers." But I have demonstrated that the 

 agency of caloric is not confined to the mere 

 separation of bodies ; that the same agent which 

 expands them into vapours and gases, enables 

 them to unite chemically with each other, to 

 form new compounds, in obedience to the same 

 law by which liquids are enabled to dissolve and 

 unite chemically with solids ; that is, by the at- 

 traction of caloric for ponderable matter. 



The most extraordinary fact connected with 

 the history of modern science is, that while 

 caloric is constantly employed in all the operations 

 of chemistry, and the arts of everyday use, 

 several distinguished modern philosophers have 

 refused it a separate numerical station among 

 the elements ; treating it as an incidental or 

 subordinate effect of those powers and changes 

 of which it is the primary and efficient cause. 



to Petersburgh. Its neck was covered with a long main, and 

 the rest of its body with black hairs and a reddish fur or wool. 

 The tusks were nine feet long, and weighed 350 pounds. For 

 further particulars in regard to this curious discovery, see Cu- 

 vier's account, extracted from the Memoirs of the Petersburg 

 Academy, and quoted by Bertrand in his Revolutions of the 

 Globe. 



