1819.] and on some other Subjects of Chemical Theory. 297 
adds confirmation to the conclusion, that these elements are in 
_ ternary union. 
Their superior alkaline energy compared with the common 
metallic oxides may obviously arise from the joint action of the 
hydrogen and oxygen, in the same manner that the acidity of 
the ternary compared with the binary acids is increased by a 
similar constitution. Thus the class of alkalies will exhibit the 
same relations as the class of acids. Some are compounds of a 
base with oxygen: such are the greater number of the metallic 
oxides, and several, probably, of the earths. Ammonia is a 
compound of a base with hydrogen. Potash, soda, barytes, 
strontites, and, probably, lime, are compounds of bases with 
oxygen and hydrogen ; and these last, like the analogous order 
among the acids, possess the highest power. Many of the . 
metallic oxides, however, in the state in which they combine 
with the greatest facility with the acids, are hydrates; that is, 
supposed compounds of the oxide with water, but probably 
ternary compounds of the metal with oxygen and hydrogen ; 
and their facility of combination may depend on this constitu- 
tion. The same principle explains the necessity, not otherwise 
easily accounted for, of the presence of water, to enable some 
of the earths, as barytes, to combine with acids. 
There are two views under which the neutral salts may be 
considered in the preceding theory. It has been shown, that 
when water is obtained in the action of a salifiable base, whether 
alkali, earth, or metallic oxide, there is reason to infer that this 
water is formed by the hydrogen and part of the oxygen of the 
acid entering into binary combinations ; and when water is 
obtained from an alkali by the action of an acid, there is the 
same reason to believe that it is formed by the combination of 
the hydrogen of the alkali with a portion of its oxygen. In 
these cases it may be supposed, that the radical of the acid 
combines with its remaining oxygen, forming a binary com- 
pound, which may still be considered as an acid; and that the 
radical of the alkali combines with its remaining oxygen, forming 
a binary compound, which may be regarded as an alkali; and 
these two compounds may unite with each other, forming the 
neutral salt. This is conformable nearly to the common doc- 
trine. But there is another point of view under which the 
subject may also be considered. A ternary combination, into 
which oxygen and hydrogen enter, gives rise apparently to a 
higher state of acidity, and to a greater degree of alkaline 
energy than is acquired from a mere binary combination into 
which oxygen enters. It is doubtful, therefore, if such binary 
compounds were formed, if they would constitute either acid or 
alkali. And there is at least no proof of their formation. In 
all these cases, while the hydrogen present combines with the 
requisite proportion of oxygen forming water, the radical of the 
cid and the radical of the base may enter ito union with the 
