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3. Water as a solvent or menstruum, modifying, in proportion to its quan- 

 tity, the chemical power and functions of the compound held in solution. The 

 complete and equable diffusion of a soluble body, by which its characteristics 

 are manifested through the medium of this fluid, may be regarded as the effect 

 of a contiguity resulting from molecular rather than atomic attraction. In 

 this case, the pair of hydrogen atoms are designated by the letter A, and the 

 oxygen atom by t ; and th, as a prefix to the name of a compound, denotes 

 that such compound is held in solution by an indefinite quantity of water. 

 Any amount corresponding to a definite number of molecules of water may be 

 represented by the usual vowels placed before th. The following brief exhibit 

 of names will show the economy and precision of expression applicable to 

 substances now commonly called and recognized only by misnomers. 



A solution of hydrochloric acid and water, thalad. 



Fuming solution containing 43 per cent of HC1 or 6 aqua, eatha/ad. 

 Solution of HC1 which distils unchanged (20 per cent acid, or 16 aqua), authalad. 



Hydrate of chlorine,5/H 2 Qfcl uthad. 



Sulphuric acid, distinguished as oil of vitriol, elasot. 



Sulphuric acid with indefinite quantity of water, thelasot. 



Glacial sulphuric acid, athelasot. 



iNitric acid, indefinite solution by water, thalanit. 



Nitric acid, solution containing 60 per cent NOs or 3 aqua, ithalanit. 



Solution of ammonia and water, thilan. 



Solution of alcohol and water, thechelat. 



Solution of carbonic anhydride (soda water), tharet. 



In the further progress of chemical investigations, increasing significance 

 must be given to the state of dilatation of the body under examination. On 

 passing from the solid to the liquid state, its bulk will undergo but compara- 

 tively little change. In either state, the restless particles which make up the 

 apparently unmoved mass are still obedient to the law of cohesion, although 

 in the liquid the league of homogeneity is not so binding as to prevent the 

 admission of foreign matter ; but when, by the irresistible power of the almost 

 infinitesimal motions of a subtle medium, heat accelerates and amplifies the 

 excursions of particles until they fly simultaneously beyond the dominion of 

 a common attraction, it must be admitted that the mass thus expanded to the 

 gaseous state in reality a vast reservoir of molecular momentum requires 

 some distinctive appellation. It is therefore proposed to denote every gaseous 

 compound, and every volatile body after it has fumed into vapor, by simply 

 prefixing to its new name the letter g. 



Were it desirable to show the degree of condensation of gases produced by 

 their combination, the number of volumes included in one molecule could be 

 indicated by the usual vowels before g ; but as the number of atoms now 

 conforms to the number of volumes of gaseous elements, in most cases, the 

 amount of condensation can be easily estimated. At present it seems essential 

 only to indicate that the molecule has assumed a state of gas or vapor. 



The succeeding names are illustrations : 



