126 
Selected Articles. 
finally, were totally discarded in favour of narcotine and 
morphine. 
Since 1817, the opinions entertained of the composition of 
opium, and of the therapeutic influence exercised by each of 
its constituent principles, remained much the same. Thus, 
in a thesis maintained before the School of Pharmacy, by 
M. Decoudemanche, in 1821, he states that the relative value 
of the different preparations of opium may be estimated by 
the proportion of morphine and narcotine contained in them. 
Very lately, however, the well proved existence of volatile 
principles in opium, and more especially the discovery of 
codeine by M. Robiquet, of narceine by M. Pelletier, and of 
meconine by M. M. Dublanc, jr. and Couerbe, do not permit 
us to consider narcotine and the acid meconate of morphine 
as the only active principles in opium. It therefore becomes 
necessary to revise the statements of M. Decoudemanche, 
so as to make them harmonize with the actual state of 
science. I shall, therefore, after having established the che- 
mical composition of opium on the most recent and positive 
data, indicate the most common preparations of this article, 
and endeavour to determine a 'priori, from their known pro- 
perties, which of the constituent principles of opium should 
be found in each of these preparations, and which are to be 
modified or eliminated. 
The constituent principles of opium now generally recog- 
nized, are: 
1. Narcotine of Derosne and Robiquet. 
2. Acid meconate of morphine of Seguin and Sertuerner. 
3. Acid meconate of codeine of Robiquet. 
4. Narceine of Pelletier. 
5. Meconine of Dublanc, jr. and Couerbe. 
G. Caoutchouc of Robiquet. 
7. Bassorine of Pelletier. 
8. Sulphate of morphine of Dupuy. 
9. Sulphate of lime 1 CT \ 
— ~ ci i i r , > of Derosne. 
10. Sulphate oi potash 3 
11. Volatile matters,^ 
12. Resinous do. V of the older chemists. 
13. Gummy do. ) 
