£■58 J^Teiv Publications. 



It is elaftic and expanjlble: that it is yiot expanfihlc* : that 

 any quaptity of this fubftance poflTefles more or lefs of expanr 

 five power, according as it is lefs or more expanded : that it 

 fills all fpace, in contmuity, without interftices : that it never 

 produces fenfible heat without entering into intimate chemical 

 combination with all the parts of the heated body : that its 

 expanfive force isfometimcs aftive, fometimes inert and qui- 

 efcent : that, in vapour, caloric is, though fixed and latent, yet 

 only mechanically adherent to the vaporified fubftance ; while 

 in the permanent clafiic gafes it is ch.emically combined with 

 the refpetSlive bafes : with various other doftrines, which, as 

 lefs novel and peculiar, require not to be here particularly 

 noticed. 



Light, this author reprcfents as a compound of a peculiar 

 bafe with caloric. Ifc fuppofes it to be rendered fluid and 

 elaftic by caloric ; to be fixed, without it. He conceives light 

 to exift: in a fi^'ed ftyte in all combuftible bodies, arjd to be 

 evolved, in combuftion, into combination with the caloric 

 from the viUtl air that is then decompofed. In this manner 

 he defcribes light as the fame thing with the phlogijlon of 

 the difciples of Stahl ; not allowing that, if fixed, it muft have 

 gravity, and that, if it have gravity, the bodies out of which 

 it is evolved mult be lighter, as to their other matter, after 

 they have loft it, than while it ftill exifted in them. He rcr 

 gards it as being, though a diftinft fubftance from caloric^ 

 y-et the matter of heat, and the principle of comhujTton. 



Speaking of com.^z<//io«, Gren fcruples not to affirm, that 

 the antiphlogiflic fyjlem aflbrds no explanation of the reafon, 

 why a certain degree of previous heat is necelfary to the com- 

 mencement of flaming coitibuftion. Flame he defcribes as 

 eflentially confifting of the burning gas of the bodies which 

 are decompofed under it. 



He thinks it not improbable that gas-azot and gas-oxygerj 

 tnay co-exift in the atmofphere, not in a merely mechanical 

 mixture, but even in intimate chemical combination. 



T^sXfog waiph renders the atmofphere thick, dirr,, and 



'* See the work, Vol. I. § 151. It is poiuble, however, there may be 

 fome miftakc in the printing. 



turbid J, 



