from the same proportion of sulphat of Iron, if double the 

 quantity of acetate of Kali be employed. As Alcohol is 

 seldom to be met with except in the Laboratories of Experi- 

 mental Chemists, this mode of preparing the medicine came 

 into general use, and it was therefore thought proper to re- 

 tain it in the Pharmacopoeia, published by the Dublin Col- 

 lege. It must be observed, however, that the tincture con- 

 tains not only acetate of Iron, but also acetate of Kali; this 

 is evinced by examining the extract that remains after the 

 spirit is evaporated, which from the predominance o^f the salt 

 last mentioned, is whitish, whereas the extract of the tincture 

 by Alcohol is of a beautiful crimson colour, and appears to 

 be a very pure acetate of Iron, more perfectly neutralised 

 than most other of the metallic salts. The Alcohol tincture 

 contains more Iron than the tincture by rectified spirit with 

 double acetate of Kali. A drachm measure of this last af- 

 forded gr. if of prussiate of Iron by precipitation with a pure 

 prussiate of Kali, which scarcely turned blue on the addition 

 of an acid. The same quantity of Alcohol tincture afforded 

 gr. 11 of prussiate of Iron.* In both cases, marine acid Avas 

 added .to separate any prussiate of Iron which the redundant 

 prussiate of Kali might have dissolved. That the tincture 

 does not contain sulphat of Iron, is proved by its not affording 

 a precipitate when a solution of muriate of Barytes is added. 

 This tincture by Alcohol is inserted among the Praeparata ex- 

 temporalia of the Pharmacopceia; from an ounce measure 

 may be obtained by evaporation, with a gentle heat, about 



10 grains 



* This result is the mean of two experiments. 



