ai) 
IIl.—On the Constitution of Codeine and its Products of Decomposition. By THomas 
AnveErson, M.D. 
(Read 15th April 1850.) 
During the last few years, great progress has been made in the study of the 
organic alkalies, and the discovery of methods by which these substances can be 
artificially produced, and the long train of investigations by which it has been 
followed, has greatly extended our previous information, and afforded us some de- 
finite ideas regarding their constitution. The advance made has, however, related 
entirely to the volatile bases produced by artificial processes, and our knowledge 
of the natural fixed alkaloids stands very much where it did some years since, 
and is still very imperfect, and in regard to many entirely fragmentary; so much 
so, indeed, that of all the alkaloids of this class described in chemical works, there 
are not perhaps a dozen of which the constitution can be considered as definitely 
fixed, and not half that number of which we know the products of decomposi- 
tion. The fact is, that the interest attaching to the artificial bases has altogether 
diverted the attention of chemists from the natural alkalies, which have not 
hitherto proved a very productive field of inquiry; at least the researches to 
which many of them were subjected ten or fifteen years since, proved compara- 
tively unfruitful in their results. The want of success which attended their in- 
vestigation at that time, however, is attributable, partly to the imperfections of 
the method of analysis of such compounds, and partly to our entire ignorance of 
the constitution of the nitrogenous substances generally. Neither of these diffi- 
culties can now be said to exist ; and the investigation of the volatile bases has 
so far elucidated the constitution of these substances generally, that we are now 
in the condition to return to the examination of the far more complex natural 
bases with some prospect of ultimate success. Chemists are, accordingly, begin- 
ning to turn their attention to this field of inquiry, and during the last few 
months, several investigations have been published, by which the constitution 
and products of decomposition of several important bases have been established ; 
and in the present paper I propose communicating to the Royal Society the 
results of a series of investigations of codeine and its compounds, which has 
enabled me to add it to the number of those of which the constitution is definitely 
fixed. 
It will be unnecessary for me to premise any observations regarding the his- 
tory of codeine and its discovery, which are sufficiently well known, further than 
to refer to the analyses and formule given for it by the different chemists by 
VOL. XX. PART I. Q 
