286 
ORIGINAL COMMUNICATIONS. 
mortar, and add the water, by small portions at a time, until 
the whole is dissolved: then add the paregoric, antimonial 
wine, and other ingredients, and shake the whole together. 
No. 6. 
Gum Arabic 4 drachms. 
Extract of Liquorice 6 " 
Paregoric 4 " 
Antimonial Wine 2 " 
Hot Water 12 ounces. 
Dissolve the gum and liquorice in lumps, by means of the 
hot water; then throw upon a filter, and afterwards add the 
other ingredients to the filtered liquid. 
Brown Mixture, as commonly made, may be considered 
a very inelegant preparation, and is subject to several objec- 
tions in a pharmaceutical point of view. The principal of 
these are its extreme turbidness, aptitude to spoil, and want 
of uniformity. The powdered liquorice employed for this 
purpose is the liquorice of commerce, containing such impu- 
rities as starch, and insoluble carbonaceous matters indepen- 
dent of the copper with which it is invariably found con- 
taminated. The design of recipe No. 6 is no doubt to get rid 
of these impurities by filtration: but this I found impracticable 
on account of the gum which fills up the pores of the paper, 
rendering it impervious. The solution of the extract alone is 
very difficult to filter: the liquid passes very slowly, leaving 
behind a large quantity of the liquorice undissolved. After the 
Brown Mixture has been suffered to remain at rest for some 
time, much of the liquorice, including the insoluble portion, is 
deposited, the proportion of gum not being sufficient to keep it 
in suspension, which has led to the custom of first shaking the 
bottle, before giving the mixture, which is then thick and 
turbid. If there be a considerable increase in the quantity of 
gum, the mixture sooner decomposes, and, to remedy this? 
some make a large addition to it of paregoric and antimonial 
wine, which, besides giving a greater anodyne effectthan intend- 
ed, throws down some of the gum and liquorice. During hot 
