194 PROCESS Ot CLASSIFICATION. 



have been acquired, during the act of incorpo- 

 ration with it ; so that the system ought to be 

 considered the base, which gives the gas its par- 

 ticular character. 



Although the base from whence these gases 

 originate, is evidently to be referred to mat- 

 ter solid or liquid, and that it is the spe- 

 cific quality of the base which gives the 

 distinguishing character to each gas ; it is, 

 nevertheless, certain, that the convertibility 

 of the base to a gaseous state, whether it 

 be of a solid or liquid kind, is accomplished 

 by a power separate and distinct from any 

 inherent power resident in the base itself. We 

 have direct evidence, that not only animal and 

 yegetable matter, both solid and fluid, that 

 metallic oxydes, as well as the pure metal itself; 

 m short, that matter the most dense and solid, 

 of which we have any knowledge, in common 

 with water itself, is often converted to a ga- 

 seous state. This change which the different 

 substances have undergone, which subserve to 

 this process, is total and complete, and no traces 

 whatever of the original base can be afterwards 

 detected. 



From the concurrent evidence of our best 

 chemists, it may be stated, as far as chemical 

 analysis can be depended on that the atmos- 

 phere consists of 77-5 parts in one hundred, by 

 measure, of nitrogen gas 21 parts of oxygen, 



