ANTIDOTE TO PRUSSIC ACID. 
223 
indicate that the proper dose of the salt is forty-five grammes 
(694 grains) for a man, and forty grammes (617 grains) for 
a woman. 
In the preparation of the magnesia lemonade according 
to the above formula, the first part of the operation con- 
sists in making a citrate of magnesia with excess of acid. 
In the second part of the process, part of the free citric acid 
is saturated with the carbonate of magnesia, carbonic acid 
being at the same time set free so as to make it an efferves- 
cent water, while there is sufficient uncombined citric acid 
to give it an acidulous taste. — Pharm. Jonrn.,from Jonrn. 
de Pharm, 
ART. LX IV . — A NT I DOTE TO PRUSSIC ACID. 
By Messrs. T. and H. Smith. 
Some time since, an antidote to the poison of prussic acid 
was made known to the public by us, through the medium 
of the Lancet, of 5th October last. Subsequently, Professor 
Christison, Mr. Taylor, and other eminent toxicologists, 
have sanctioned with their approval the principle of the 
proposed antidote, which, when tried on animals, proved so 
strikingly successful. It need only be repeated here, that 
the utility of the remedy rests on the presentation to the 
deadly acid of iron in such a state of oxidation, as to form 
with it the well-known compound called Prussian blue; 
and as the latter is innocuous to the stomach, animal life 
may be preserved wherever such a combination of the acid 
