12 
LECTURES ON THE BRITISH PHARMACOPOEIA. 
time, though this statement has also been contradicted. Mr. Hemingway now 
tells me that a precipitate may or may not be formed, wdien the tincture is set 
by, and that the cause is the variable nature of the peel used in making the 
tincture of orange. If peel sufficiently good cannot now be obtained, it may be 
found necessary, in a future edition of the Pharmacopoeia, to include a small 
quantity of sulphuric acid in the formula for this tincture. 
Tinctura Rhei. The formula for this tincture is new. It will replace the 
Tinctura Rhei Composita of the London and Dublin, and the Tinctura Rhei 
of the Edinburgh Pharmacopoeias. I am told that, in this instance, the triple 
process ordered is a most excellent one. Liquorice is no longer a constituent of 
tincture of rhubarb, an omission suggested by Proctor (Pharm. Journ.2nd ser. 
vol. i. p. 11). 
Tincturse Valeriana. According to Burton, valerian is readily deprived of 
its soluble constituents by maceration in proof spirit for forty-eight hours. Sub¬ 
sequent percolation therefore, as directed in the Pharmacopoeia, is unnecessary. 
Tinctura Zingiberis. Tincture of ginger is now nearly twice the strength of 
the old London and Edinburgh preparations,—a change in accordance with a 
suggestion of Proctor (Pharm. Journ. 2nd ser. vol. i. p. 11), who urged as 
reasons for an increase in the strength, that the stronger tincture, called Essence 
of Ginger, was more in demand, and could be used for preparing Syrup of 
Ginger. 
From these notices of about one-third of the whole number of tinctures con¬ 
tained in the British Pharmacopoeia, it is obvious that the processes for their 
preparation are in only a few instances the best that could have been devised. 
The manufacture of tinctures is peculiarly the province of chemists and drug¬ 
gists,—a class whose confidence in the Pharmacopoeia would have been greatly 
increased had the volume contained good evidence that the published researches 
of members of their own body and other gentlemen had had that attention 
they deserved. 
The remaining two-thirds of the tinctures still need investigation, such as was 
brought to bear on them by Burton. 
Trochisci. —Medicated lozenges were not mentioned in the London and Dub¬ 
lin Pharmacopoeias. The Edinburgh Pharmacopoeia contained formulae for ten 
lozenges; three of these, namely, Trochisci Morphia , Trochisci Morphia etIpeca¬ 
cuanha, and Trochisci Opii , have been retained in the British Pharmacopoeia ; 
and three new ones, namely, Trochisci Acidi Tannici , Trochisci Bismutlii, and Tro¬ 
chisci Catechu, introduced. Each tannin lozenge contains half a grain of tannic 
acid ; each bismuth lozenge, two grains of white bismuth ; each morphia lozenge, 
one thirty-sixth of a grain of hydrochlorate of morphia ; each morphia and 
ipeeacuan lozenge, one thirty-sixth of a grain of hydrochlorate of morphia and 
one-twelfth of a grain of ipeeacuan ; and each opium lozenge, one-tenth of a 
grain of extract of opium. 
Unguenta.— Owing to the amalgamation of the old London cerates with the 
ointments, and the great discrepancies between several of the London, Edin ¬ 
burgh, and Dublin formulae for the ointments, this class of preparations has un¬ 
dergone considerable change. So far as can be seen at present, most of these 
changes are improvements. 
TJnguentum Aconitia is now officinal. Unguent-urn Atropice is also new to 
the Pharmacopoeia, but is not introduced to supersede Unguentum Belladonna , 
which is still retained, though the process of making it is slightly modified ac¬ 
cording to the suggestion of several pharmaceutists. Unguentum Cantharidis 
is apparently a compromise between the London Ceratum Cantliaridis , the 
Edinburgh Unguentum Infusi Cantharidis , and the Unguentum Cantharidis 
of the three Pharmacopoeias. Unguentum Cetacei is the London preparation 
with almond oil in the place of olive oil, as suggested by Deane and others 
