On the "Preparations of Opium. 133 
rtioned preparations may then offer special advantages, but it 
.by no means follows that they are of equal value. 
In the first place, it must be conceded that such of the pre- 
parations of opium, which, like the extracts and laudanum 
made by fermentation, are prepared by manipulations which 
do not always afford identical products, have a marked dis- 
advantage. In the next place, there are others which appear 
to present so much analogy of composition, on account of the 
methods by which they are prepared, that it is rational to 
suppose that they may be used for the same purposes. To 
this class belong most of the watery extracts. 
It is therefore necessary to fix the best method of forming 
the first, and to determine of chemical and physiological ex- 
periments, if among the latter, that which is the most readily 
made, possesses any advantage over, or is equal to the others. 
Researches of this kind, in my opinion, will be of greater ad- 
vantage to the pharmaceutic art, than the introduction of new 
•preparations of the article under consideration, which in a 
•few years are perhaps destined to become as problematical 
as their predecessors. I am confident that nothing is more 
•prejudicial to our art than the great increase of new prepara- 
tions, which do not produce either immediate principles pos- 
sessed of unvarying properties, or combinations faithfully 
^presenting the primary article. 
Journ. de Pharm* 
