302 
REVIEW. 
change of this kind the names of such salts as those alluded to would be rendered not 
only more consistent with each other, but also more consistent with the existing views 
of scientific men. But even this system of nomenclature fails to accomplish all that is 
required, and Dr. Attfield does not apply it in all cases. In some cases it does not ex¬ 
press enough, and perhaps we might add that in others, if not in all, it expresses or 
conveys too much. The name sulphate of iron, for instance, is not sufficiently explicit, 
because there are two sulphates, and the name does not indicate which is meant. We 
cannot distinguish them as we have been accustomed to do by calling one sulphate of’ 
protoxide and the other sulphate of peroxide of iron, because we deny the presence of 
oxide in both. To meet this difficulty another sort of name is adopted in such cases, 
and the two sulphates of iron are respectively called ferrous and ferric sulphate. Tt may 
be asked why, if another sort of name is required in such cases as this, names similar to 
the latter should not be applied in all cases, and sulphate of potash and sulphate of 
copper he called potassic sulphate and cupric sulphate. This, in fact, is done by many 
modern chemists, and it constitutes what appears to be the most approved system of 
nomenclature of the present time ; but such a system, while it answers very well for 
scientific purposes, is not well suited to the requirements of pharmacy. We want names 
that can be Latinized and that can be abbreviated without being rendered unintelligible. 
Consistency and even simplicity must therefore be sacrificed, and the author, in spite of 
himself, is obliged to make such a sacrifice in favour of convenience. While sulphate 
of potash, therefore, is changed to sulphate of potassium, sulphate of mercury is 
changed, according to a different system, to mercuric sulphate, and the two chlorides of 
mercury are called mercurous and mercuric chloride, names which it is very undesirable 
to introduce in pharmacy. But the proposed new names, composed of the name of a 
metal associated with a word representing a radical to which’ the metal is supposed 
to be united, while they sometimes fail to express enough, at other times express too 
much, or do not express the right thing. Thus, the name hydrate of potash has been 
applied to solid caustic potash under the impression that it consisted of oxide of potas¬ 
sium (potash) combined with water, forming a definite hydrate ; but this name is 
changed to hydrate of potassium by modern chemists, who deny that caustic potash 
necessarily contains any water. The name ‘hydrate,’ therefore, although strictly and as 
hitherto used it signifies a body containing water in combination, is now used in a 
different sense. The new symbolic formula for caustic potash is K H O, and as O here 
represents the new atomic weight of oxygen = 16, the H O represents not water but 
peroxide of hydrogen. The author says, ‘"HO is characteristic of all hydrates,” or, 
in other words, all hydrates are compounds of peroxide of hydrogen. This, at least, is 
the meaning that would be generally put upon the explanation given, but possibly what 
is meant is, that HO is the group of symbols and not the group of atoms characteristic 
of a hydrate. Following the definition he has adopted for hydrates, he represents the 
hydrated oxides of iron as compounds of iron with peroxide of hydrogen, so that they 
neither contain water nor are they oxides in the ordinary sense of the word. 
But then, on the other hand, he designates the compound (MgC O a , 3H.D), that is. 
carbonate of magnesia with three atoms of water, as ter-hydrated monocarbonate of 
magnesium. It would thus appear that while a hydrate is a compound of peroxide of 
hydrogen, or at any rate is symbolically represented as such, a hydrated body is a com¬ 
pound containing water. Nor is this the only sort of case in which the proposed new 
nomenclature, when indiscriminately applied, leads to confusion and inconsistency by 
expressing or conveying more than is wanted or intended. The author evidently feels 
this difficulty, and makes the following sensible remarks on the constitution of salts :— 
“ It is here necessary again to caution the reader against regarding salts as invariably 
possessing a known constitution, or supposing that they always possess two or more 
.sides, or contain definite radicals. The erroneous conception which, of all others, is most 
likely to be imperceptibly formed, is that of considering salts as binary bodies. For, 
first, the names of salts are necessarily binary. A student hears the names ‘ sulphate of 
iron,’ ‘ sulphate of copper,’ and simultaneously receives the impression that each salt has 
two sides, copper or iron occupying one, and something indicated by the words ‘sulphate 
of,’ the other. The words ‘vitriol,’ green or blue, ‘nitre,’ etc. would perhaps implant 
unitary ideas in his mind; but it is simply impossible to give such names to all salts 
as will convey the impression that each salt is a whole, and therefore unitary. The 
name ‘ sulphate of potash ’ produces binary impressions; and the less incorrect name. 
