July 29,1971.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
81 
THE STRENGTH OE TEE HYDROCYANIC 
ACID OF PHARMACY. 
RY DR. W. A. TILDEN. 
tity of pure wax; but, being told that it would be 
! submitted to a competent analysis, wrote, stating 
their regrets that they had no “ pure ” at present in 
stock. 
Having on several occasions noticed considerable 
deficiencies in the strength of hydrocyanic acid said 
to be B.P., that is represented as containing 2 per 
cent, of real acid, I have recently examined a few 
samples, with the view of comparing them together, 
and of ascertaining how far they diverge from the 
Pharmacopoeia! standard. 
A weighed quantity wars in every case introduced 
into a stoppered bottle containing water, and more 
than sufficient potash to convert all the HCN into 
KCN. An accurately standardized solution of ni¬ 
trate of silver was then run in from a burette, till, 
after shaking, the last drop produced a faint opacity 
of the fluid. As in most cases two experiments 
were performed with the same sample, the close 
agreement of the results shows the accuracy of the 
method. 
Kb. 
Percentage of H C X. 
1. . . 
. . . 2T83 
2-188 
0 
rw • • • 
. . . 2-037 
2-028 
3 . . . 
. . . 1909 
4 . 
. . . 1-521 
1-520 
5 . 
. . . -980 
0 . . . 
. . . -903 
'904 
7 . . . 
. . . *789 
*790 
8 . . . 
. . . -483 
•484 
The first three are what they should be ; the 
fourth is only three-quarters of the strength re¬ 
quired officially; the last four are quite unfit to use, 
and should be condemned. Pharmacists who em¬ 
ploy for dispensing purposes hydrocyanic acid in 
such a condition as these four samples should not 
forget that they take upon themselves the responsi¬ 
bility of reducing the dose ordered by a medical man 
in his prescription to one-half, or as in the last case 
to less than one-fourth. 
It is difficult to suggest a remedy for this kind of 
thing. The practice of testing all the more impor¬ 
tant preparations, both qualitatively and quantita¬ 
tively, must become more common than hitherto 
among retail druggists; and in the case of articles 
like prussic acid, which is cheap, easily prepared, 
and in the dispensing of which accuracy is specially 
demanded, it seems desirable to renew the stock 
often enough to avoid changes of such a serious 
character. 
THE OPTICAL ANALYSIS OE BEES¬ 
WAX. 
BY HENRY TOCKLINGTON, HULL. 
A brief resume of my observations and experi¬ 
ments in the optical analysis of Cera Jiava and 
C. alba, as found in the trade, may not perhaps be un¬ 
interesting or wholly valueless. It lias been remarked 
to me that pure wax is not to be obtained in large 
quantities, and that wholesale dealers feel them¬ 
selves secure against detection, provided they re¬ 
strict their choice of adulterants within certain 
limits. To some considerable extent this is true; 
to so great an extent, indeed, that out of the very 
numerous samples that I have examined, all said to 
be “ pure,” there was not one but was more or less 
largely adulterated; and I have knowledge of firms 
who professed themselves able to supply any quan- 
Tiiird Series, No. 57. 
During a conversation on microscopical subjects 
with my friend Mr. C. P. Gibson, M.P.S., of this 
town, this beesv r ax question cropped out, and my 
friend, himself an ardent microscopist, produced a 
number of slides of Cera jiava and C. alba for my 
inspection, remarking, “ they are all said to be pure, 
but one, at least, is very remarkable as regards the 
form of the crystals.” A cursory glance convinced 
me that one specimen was very adulterated, and 
none of them, least of all the C. alba , appeared to 
me to be genuine. To obtain a sample of pure wax 
was now our difficulty, from which Mr. Gibson’s 
assistant speedily extricated us, by obtaining from 
some friends who were beekeepers a small portion 
of absolutely unadulterated wax that had been pne- 
pared by them for their own use. My friend most 
kindly undertook to prepare for me, according to my 
directions, a series of slides, some being pure, others 
adulterated in defined proportions with suet, lard 
and stearine, the whole being put up in a similar 
manner, and carefully labelled. A slight examina¬ 
tion of these slides by means of the microscope 
would show the least experienced observer that a 
slide of pure wax was a far less pretty microscopic 
object than a slide prepared from ordinary commer¬ 
cial wax. But this is hardly enough. More is re¬ 
quired than a slight difference in prettiness to enable 
us to pronounce decidedly upon the presence or not 
of an adulterant. For example, it might be objected 
that the two slides were prepared from wax of a 
different nationality, and that the very different food 
of the bees in the one country caused a variation in 
the beeswax, which was shown by the slightly dif¬ 
ferent arrangement of the crystals as seen under the 
micropolariscope. To satisfy myself that this was not 
a misleading element in the affair, I examined a con¬ 
siderable number of samples of commercially pure 
wax under a Beck’s p-inch objective, using a Nichol 
prism for polarizer, and an exceedingly good tour¬ 
maline as an analyser. Under the \ -inch, the form of 
the crystals in commercial wax, as in pure, are seen 
to maintain a strong individuality. The wax crystal 
is smaller, always less feathery in aggregation, and 
has slightly different (as yet undetermined) rotative 
powers. The wax crystals in an adulterated or 
commercial specimen can almost be pointed out one 
by one to an observer by means of an indicating 
eyepiece. Their separation is most complete and 
distinct. It is not easy, without carefully-executed 
drawings, to point out the difference between the 
forms of wax crystals and those of the stearine (in 
some form or other) with which wax is invariably 
adulterated. It may serve my purpose here, which 
is merely to suggest a means by which every che¬ 
mist may act as his own detective in this matter, if 
I describe my mode of procedure. 
The only requisites are a microscope of tolerably 
good workmanship, such as may be purchased of 
any of our leading opticians for a few pounds. The 
stage should either be itself capable of rotation or 
receive Swift’s Blankley’s* revolving stage, an ex- 
* It is due to these gentlemen that I express my thanks 
for the courtesy with which they have placed apparatus at 
my disposal in working out certain microscopic problems, 
and in carrying out my suggestions. 
