ANALYSIS OF THE ROOT OF RHEUM AUSTRALE. 283 
peared to him that the results had a close analogy with those 
obtained from an examination of the exotic articles from China 
and Russia; which is strong corroboration of his opinion 
with respect to the origin of the latter. As the Rheum aus- 
trale had attracted the attention of naturalists, it was of im- 
portance to experiment upon its cultivation in France. M. 
Merat, a member of the Royal Academy of Medicine and a 
distinguished physician, has prosecuted this task with peculiar 
diligence, and was enabled some time back, to present to this 
learned body many specimens of the recent roots of the 
Rheum australe, raised near Paris. 
Having been requested to make an analysis of these roots, 
I have bestowed especial care upon the undertaking, which, in 
my estimation, was of importance; and, with the hope that the 
results will not be uninteresting to pharmaceutists, I have de- 
termined to publish them. 
Before entering upon the subject, I shall present a short 
notice of the numerous publications upon the rhubarb from 
China and Russia, by MM. Henry, sen., and Guibourt, Shra- 
der, Brandes, Caventou, Peretti, and finally by Hornemann, 
whose more recent experiments will be of service to me, 
in the way of comparison. Upon examining the results 
obtained by these authors, it will be perceived that they exhibit 
little agreement ; but a reason for the differences between 
them can be advanced, by supposing that on the one hand the 
specimens of rhubarb analyzed, had not been identical, and on 
the other, that the methods of analysis pursued, had not always 
been the same; hence marked dissimilarity in the isolated 
products naturally occurred. It is moreover known, that 
many of these products are complex, and result from the union 
of several others; it is therefore easily understood why they 
are more readily separated from each other by one method, 
than by another; and how it is that in one analysis, it may be 
the yellow resin which predominates, whilst in another, it 
may be a bitter substance, or a principle analogous to gum, &c. 
Sometimes we meet with the oxalate of lime, as one third 
component of the rhubarb, whilst at others this salt is not de- 
