515 
PHARMACEUTICAL SOCIETY, EDINBURGH. 
of the enormous price at which it is valued by the Chinese, and the remarkable 
virtues ascribed to it. But as is the case with many similar substances (of 
which we are not without parallels in European medicine) the value of this 
drug proved to be due, not to its peculiar properties, so much as to the super¬ 
stition and ignorance of those who sell or administer it. 
The first sample I received was accompanied with the inquiry if it were not 
iodide of potassium, and had it been that substance one could hardly be sur¬ 
prised that even twenty dollars an ounce might be paid for it. It was a rounded 
fragment of a substance of dark colour and compact crystalline structure, which 
chemical examination proved to be chloride of sodium. Since his return from 
China, my friend Mr. Lockhart has kindly placed in my hands a more ample 
supply of this substance, the examination of which has shown that though 
essentially chloride of sodium, it contains traces of alkaline sulphuret, and that 
it resembles in composition and general appearance one of the forms of impure 
chloride of sodium found in the bazaars of India under the name of Black Salt. 
Tatarinov in his ‘Catalogue of Chinese Medicines’* represents the name 
Naou-sJia , to be applied to sal ammoniac of volcanic origin, and in Pekin at 
least such is truly the case. When my friend Mr. Lockhart was residing in 
that capital in charge of the hospital established under the auspices of the 
London Missionary Society, he took the opportunity of making some inquiries 
regarding the drug in question, and very recently he has handed me several 
specimens of it obtained in the Pekin shops. The information Mr. L. eli¬ 
cited was not very copious, in fact all he could learn amounted to this,—that 
Naou-sha is brought from certain volcanic springs in the province of Sze-chuen, 
and in Thibet, and that the various kinds of it, differing from one another chiefly 
in their degrees of purity, are distinguished by the names Naou-slia , Yen-naou , 
and Shih-naou. 
The specimens received from Mr. Lockhart were of three kinds, the purest of 
which consisted of a compact, crystalline, colourless, saline mass, which analysis 
proved to be chloride of ammonium. The second kind was also chloride of am¬ 
monium but of different appearance, having more of the aspect of a natural pro¬ 
duction than the first. The third specimen was likewise chloride of ammonium, 
but much contaminated with earthy matter. 
There can be no doubt, I think, that this Chinese sal ammoniac is a volcanic 
product, such as is known to occur on Etna, Vesuvius, and Hecla, as well as in 
the vicinity of ignited coal-seams. Whether it is by ignorance or design that 
the Chinese confound with an impure form of common salt, I cannot affirm; but 
the circumstance calls to mind the fact proved by Beckmann,f that the sal am¬ 
moniac of the ancients was common rock-salt, dug from pits near the temple of 
Jupiter Ammon in Egypt, and that the name was subsequently transferred so 
chloride of ammonium manufactured in that country from the dung of camels. 
PHAEMACEUTICAL SOCIETY, EDINBUBGPI. 
A meeting was held in St. George’s Hall, on Wednesday evening, March 15th, at 
9 o’clock; Mr. Kemp, President, in the chair. 
Mr. D. R. Brown, Vice-President, made a communication ' on Specific Gravity, and 
illustrated many of his observations by sundry experiments. At the conclusion of Mr. 
Brown’s address, Mr. Stevenson, F.R.S.S.A., entered more fully into the practical part 
of the subject, showing and explaining a great variety of instruments foimerly in use, 
as well as most of those at present recognised by distillers, brewers, and others. Amongst 
the most interesting illustrations were some very ancient, and now obsolete contrivances for 
taking specific gravity, and Mr. Stevenson’s own simple but ingenious invention, which 
* Catal. Med. Sinens., p. 41. 
f History of Inventions and Discoveries. 
