Evistence of Radicals in the Amphide Salts disproved. 259. 
Of Liebig’s “ Principles,’ so called. 
90. Under the head of the “theory of organic acids,” in Liebig’s 
Treatise on Organic Chemistry, we find the following allegations 
dignified by the name of principles. Manifestly they must tend 
to convey a false impression to the student, that hydrogen has 
a peculiar property of creating a capacity for saturation, instead 
of being only the measure of that capacity, as is actually true, 
and likewise that in this respect it differs from any other radical. 
91. The allegations to which I refer are as follows, being a 
literal translation from the French copy of the Traité of Liebig, 
page 7 :— 
“<The hydrated acids are combinations of one or more elements with 
hydrogen, in which the latter may be replaced wholly or in part by 
equivalents of metals.” 
“The capacity of saturation depends consequently on the quantity of 
hydrogen which can be replaced. 
‘“‘' The compound formed by the other elements being considered as 
a radical, it is evident that the composition of this radical can exercise 
no influence on the capacity of saturation. 
“The capacity of saturation of these acids augments or diminishes in 
the same ratio as the quantity of hydrogen, not entering into the salt 
radical, augments or diminishes. 
“Tf into the composition of the salt radical there should be introduced 
an undetermined quantity of any elements, without changing the quan- 
tity of hydrogen extraneous to the radical, the atomic weight of the 
acid would be augmented, but the capacity of saturation would remain 
the same.” 
92. As by the advocates of the existence of “salt radicals,” 
hydrogen is considered as playing the part of a metallic radical, 
and must, therefore, as respects any relation between it and the 
capacity of saturation, be in the same predicament as-any other 
electro-positive radical, I cannot conceive wherefore laws, which 
affect every other body of this kind, should be stated as if partic- 
ularly associated with hydrogen.* 
* There is, in some respects, a coincidence so remarkable as to the part taken 
by Dr. Kane and myself, with respect to hydrogen, that I quote here the language 
which has been held by us respectively on this subject. 
Treating of hydrogen, Dr. Kane uses the following words :—“ It was at one 
time supposed that it shared with oxygen the power of generating acids; and as 
sulphur, chlorine, iodine, cyanogen, &c., formed one class by combining with oxy- 
gen, so they formed a second class, called hydracids, by entering into union with 
