176 
BRITISH PHARMACEUTICAL CONFERENCE. 
Tlie author feels that he has not worked out the subject as it deserves ; in¬ 
deed, so much more work remains to be done, requiring more time than he has 
at his disposal, that having made public the modus operandi , he hopes some one 
will continue its developement. 
Table of Angles. 
Name of Crystal. Predominating Angles. 
Sulphate of magnesia .... 120° 4' . . 105° 
Bicarbonate of potash .... 90° . . 128° 5' 
Nitrate of potash.76° 30' . . 103° 30' 
Ammonia alum.90° . . . 120° 
Tartaric acid.97° 10' .. 83° 30' 
Oxalic acid.74° 2' . . 106° 8' 
Cholesterine.79° 30' . . 100° 30' 
In the absence of the author, this paper was read by Mr. Schacht. 
The President expressed his admiration of the able paper that had just been read, 
which was a valuable addition to the series of microscopic investigations relating to 
pharmacy already brought before the Conference at the meetings of previous years. The 
paper was worthy of a place with the well-known and highly valued monographs on 
subjects of microscopic pharmacy by his friends Messrs. Deane and Brady, and he trusted 
that its publication would stimulate others to work in this promising field. 
Mr. Brady added his tribute of gratification at Mr. Stoddart’s labours. When that 
gentleman named the matter to him upon the occasion of the Bath Conference, it was 
new to him (Mr. B.), but he had subsequently made some experiments. He had to con¬ 
fess that one result of these experiments was to impress him strongly with the difficul¬ 
ties which at present existed to obtaining uniform results. It would be evident to every 
one, that there was a great difference between measuring the angles of a tangible and 
large crystal on the one hand, and of measuring a crystal of microscopic proportions ; the 
former could be handled and placed in any position, but the alteration of position in the 
latter case was a matter of great difficulty, or might be impossible. He felt uncertain 
how far the forms of crystals would be modified by the presence of foreign matter, as 
for instance, viscid substances in the solutions. Mr. Brady alluded to a rotating object- 
holder, introduced by Messrs. R. and J. Beck and Co., as likely to facilitate such opera¬ 
tions as those now under consideration. In connection with the solubility of salts, he 
also spoke of Storer’s ‘Dictionary of Solubilities ’ as a very valuable work, just published 
in the United States. 
NOTES ON TINCTURA OPII AND LIQ. OPII SEDATIVUS. 
BY MR. ALFRED SOUTHALL, BIRMINGHAM. 
In continuation of a subject which was brought forward at the last meeting 
of the Conference, viz. the analysis of various specimens of ordinary commer¬ 
cial opium ; in order, further, to show the extremely uncertain medicinal value 
of different samples, I have since examined a variety of specimens of tincture 
of opium, some of which have been kindly forwarded to me by Dr. Attfield. 
These specimens were, I believe, procured indiscriminately from the establish¬ 
ments of various pharmaceutists, and show a variation in strength which may 
well rather alarm the prescriber for the welfare of his patient. 
Taking the standard of strength required by the -British Pharmacopoeia, 
which states that 100 grains of opium should yield at least 6 to 8 per cent, of 
morphia, the consequent strength of tincture of opium, B.P., should be not less 
than 0 5 per cent, of morphia. The following is my result of nine samples of 
tincture:— 
