98 



Constitution 

 of gasses. 



Bodies con- 

 tain different 

 quantities of 

 caloric. 



rompositirn 

 of iiitiic acid. 



ON THE EFFECTS or HEAT. 



be produced, if the attraction of the particles for each other 

 be diminished : for in this case the atmospheres will ex- 

 pand. Either of these causes, or both combined, will occa- 

 sion the body to become fluid ; for the deiisity of the at- 

 mospheres will decrease as they exteqd : and thus the 

 motion of the particles will be facilitated. The form of the 

 particles also will influence the fluidity of the body. The 

 more spherical these are, the less resistance will there be t* 

 their motion. Hence, to form a perfect fluid, the particles 

 »iust be perfectly spherical, and placed at such a distance 

 from each other, that the density of their atmospheres, 

 where they come into contact, shall be : and this distance, 

 probably, must be infinite. It must now be clear, that the 

 specific gravity of fluids may be very various, and also 

 that they may contain very variable quantities of caloric. 



If we suppose the affinity of the particles ef the body to 

 be still farther diminished ; or the sphericity of their at- 

 mospheres to be increased by a fresh addition of caloric; 

 it will necessarily assume the state of a gas. A gas then is 

 a more perfect fluid than a lio.uid is. Gasses also may 

 contain variable quantities of caloric, and vary in specific 

 gravity. 



From all that has been said, it must be evident, that a 

 solid may contain more caloric than either a liquid or a 

 gas ; and, of course, that the quantity contained in a liquid 

 may exceed that in a gas. But the same body, when solid, 

 will contain less caloric than when liquid ; and less whea 

 liquid than in the gaseous state. It is also clear, that the 

 specific gravity of a solid may be less than that of a liquid ; 

 and it is even possible^ that the specific gravity of solids and 

 liquids, maybe less than that of some gasses. 



We have seen the combustion of oxigen and hidrogen 

 explained according to this theory ; let us examine, how it 

 accords with other chemical phenomena. 



When azote and oxigen are mixed in due proportions, 

 and an electric shock is passed through the mixture ; the 

 atmospheres of those particles, through which the shock 

 passes, are rendered of a uniform density, and the particles 

 unite. But the combustion does not spread throughout 

 the whole mixture ; be«ause the particles which combine 



do 



