RELATION OF THE BRITISH FHARMACOPCEIA TO PHARMACOLOGY. 563 
'Concession enough in omitting the word purum from the name of their acid ; for 
Redwood also said, “ the name acidum nitricum purum is a misnomer, for how¬ 
ever pure the acid may be when first prepared, it soon becomes contaminated 
with nitrous acid.” According to the principal Editor of the British Pharma¬ 
copoeia (Lancet, 1864, vol. i. p. 137), the chemistry of the work was entrusted 
to two gentlemen, one a Member of the Edinburgh, the other of the Dublin 
sub-committee; in this circumstance perhaps is to be found an explanation of the 
predilection evinced for that nitric acid which the compilers of the last London 
Pharmacopoeia had rejected as inconvenient, unstable, and in every respect dis¬ 
advantageous in comparison with the weaker one they in that work adopted. A 
writer in the ‘Medical Times and Gazette,’ 1864, vol. i. p. 291, states that two 
conflagrations have occurred through this strong nitric acid having come into 
contact with straw during transportation ; it is to be hoped, therefore, that by 
way Gf relieving any anxiety that such a statement might produce, our northern 
manufacturers will soon give us the result of their experience of the packing and 
carriage of this acid. 
Acidum Phosphokicum Pilutum. —The old process, oxidizing phosphorus 
by nitric acid, is retained. This is not a satisfactory process; a great explosion 
once occurred (Chem. News, vol. iv. p. 83) while performing it. Eisner, who 
relates the circumstance, supposed that the cause was the sudden evolution and 
combustion of phosphoretted hydrogen, a product of the decomposition of phos¬ 
phorous acid vapour into that gas and phosphoric acid ; he recommends that the 
operation be performed in an open dish, a precaution that might well have been 
adopted in the Pharmacopoeia description of the process ; for the use of the glass 
retort and Liebig’s condenser there recommended is simply to economize nitric 
acid. It is true, that if made in an open vessel the product would be more likely 
to vary in strength than if made in a retort, and the process would still be open 
to great objection. In fact, a new process altogether is much needed. Groves 
(Pharm. Journ. vol. xvii. p. 510) has suggested the employment of red phos¬ 
phorus. Neustadt (Chem. News, vol. iv. p. 13) proposes to make the medi¬ 
cinal acid by decomposing phosphate of baryta by sulphuric acid ; and Proctor 
(Pharm. Journ. vol. i. 2nd ser. p. 9) thinks it should be made by diluting the 
glacial acid ; indeed, it is stated (Lancet, 1864, vol. i. p. 361) that it is so made 
from glacial acid imported from Germany, but that such an acid will not do for 
making Syrupus Ferri Phosphatis. Probably, however, if the acid were boiled 
or kept in solution for some time, so as to convert the mono- into ter-hydrated 
or common phosphoric acid (Maisch, Pharm. Journ. 2nd ser. vol. iii. p. 278), 
there would be no objection to its use in making the iron sj-rup. A Member of 
this Society is, however, working out the subject (Pharm. Journ. vol. v. p. 491), 
so that we may hope soon to hear something satisfactory concerning it. 
Acidum Sulphuricum. —To effect the purification of commercial sulphuric 
acid we are ordered to distil it; an operation somewhat troublesome, but which 
can be accomplished if strips of platinum or quartzite (Pharm. Journ. vol. vii. 
p. 232) be put into the retort, and the latter be heated by the flame of a ring 
gas-burner in such a manner that the heat only impinges against the sides of the 
retort, unpleasant soubresauts being thus avoided. Distillation will certainly en¬ 
able us to get rid of one of the three chief impurities,—lead. It is next assumed 
in the Pharmacopoeia that nitrous compounds are always present in commer¬ 
cial sulphuric acid, and to eliminate them we are to adopt Pelouze’s proposition 
(Pharm. Journ. vol. xiii. p. 41) of distillation with sulphate of ammonia, which, 
re-acting on them, gives, apparently, water and nitrogen, the latter escaping as 
gas. Now nitrous compounds are not always present in commercial sulphuric acid, 
and therefore the absence in the Pharmacopoeia of any directions as to testing 
the specimen before distillation entails the trouble of a difficult and, to some 
-.extent, dangerous operation where it may not be necessary; for in all Pharmaco- 
