136 EXPANSION AND CONTRACTION. 



pheres at 60 F. while the bisulphuretted hydro- 

 gen becomes liquid, or semi solid, without any 

 pressure. 



By the affinity of ponderable matter for caloric, 

 its atoms are approximated and held together : 

 by its elastic or self-repelling property, it sepa- 

 rates them from each other, as in gasefaction, 

 explosion, and all decompositions. The fact that 

 Philosophers have overlooked this affinity by 

 which caloric is concentrated around the parti- 

 cles of liquids and solids, resolves the problem of 

 contradictions by which the theory of caloric has 

 been so long perplexed, and explains why many 

 have doubted its materiality why the phenomena 

 of combustion, explosion, cohesion, and chemical 

 affinity have not been understood. 



I have shown, that caloric is the cause of re- 

 pulsion in steam and all gases ; in vaporization, 

 combustion, and the expansive force of detonating 

 compounds : and that this elastic force is coun- 

 teracted and diminished, or vanquished by its 

 affinity for gravitating matter. 



The ancient philosophers of Greece often re- 

 ferred to an agency, by which they supposed 

 that all nature was perpetually tending to a ge- 

 neral dissolution: but being restrained by the 

 overpowering concord of things, (by which they 

 meant attraction,) the result of the conflict was 

 the beautiful order and harmony of the world. 

 This doctrine throws a clear and full light on 



