46S 
PHARMACEUTICAL MEETING. 
by which the product, in hydrocyanic acid value, is less than half when similar 
leaves are used fresh ; distillation, too, has always been effected by steam-heat 
of a temperature of about ‘235°, the rapidity or slowness at which distillation is 
carried on, having, doubtless, an effect upon the distillate. 
The three periods at which I have made the water have been March, July, 
and November ; the highest strength of prussic acid being obtained in March, 
when it reached 1-26 grs. of real acid in 1000 grs. ; the lowest in November, 
when it was only half the strength, -64 grs. of real acid in 1000 grs. ; the dis¬ 
tillate of July being nearly a medium between these—T08 grs., real acid, in 
1000 grs. 
The various distillates were examined from time to time ; it was found they 
had depreciated as much as 1.0, and in some cases 20 per cent, of the original 
quantity of acid. This depreciation in value of acid by age, and variable 
strength of the water, as obtained from leaves at different periods of the year, 
led me to suppose, that if I examined the cherry-laurel water in the pharmacies 
in town, I should find such a difference as should not exist with such a powerful 
remedy, which is about one-twentieth of the strength of the dilute hydrocyanic 
acid of the Pharmacopoeia. I found aq. laurocerasi varying as 53 does from 
100, or some only about half the strength of others ; in one case I found, upon 
obtaining a second specimen from the same source (within seven days) that 
water dispensed one week was but a little more than half the strength of that 
of the previous week. 
Such discrepancies as these ought not to be found, and must not exist, if we 
wish to have uniformity in medicine, and the life of the public safe in our 
hands. 
To be hard upon ourselves, “ they manage these things better in France,” for 
I have found that the Codex directs that the leaves should be gathered from 
May to September, that the distillation shall be conducted immediately (10 per 
cent, less leaves being added than in our formula), that the product shall be ex¬ 
amined and brought to a uniform strength of 50 millegrammes in 1000 c. c. 
In this respect, therefore, we might surely with advantage imitate the French, 
presuming it is absolutely necessary that we should have such a preparation 
officinal ; if not, resort to the 2 per cent, solution of hydrocyanic acid, which 
now is always to be had definite, I trust, and if required to be made more 
grateful, there are doubtless many harmless aromatic waters that will admirably 
answer the purpose. 
To the medical practitioner, however, this change must be left; the allusion 
on our part to the uncertainty of the strength of this preparation, is all that 
becomes us as purveyors of medicine. 
Laboratory , 40, A Idersgate Street , E. C. 
Dr. Redwood thanked Mr. Umney for contributing this paper, and desired 
to express his concurrence with most of the statements made in it. He looked 
upon cherry-laurel water, as an article of pharmacy, in the light of an abomi¬ 
nation ; he always had viewed it in that light, and had always protested against 
its being retained in the Pharmacopoeia ; but he had been met by the statement 
of medical men that they had been accustomed to use it, and whatever chemists 
might say about the variableness of its composition, they had found certain ad¬ 
vantages attach to its use, and wished to be allowed to use it. To such a state¬ 
ment, what answer could be made? He had long ago obtained results similar 
to those described by Mr. Umney, and had fully satisfied himself that cherry- 
laurel water was a most uncertain and variable preparation. They had been 
told, however, that great value was attached to it on the Continent, and also 
that those who had used it in this country had found a benefit from it which 
they had not experienced in the use of hydrocyanic acid, and they were also 
