/ 
On the ligneous Part of Gray Ipecacuanha. 3 
contain this principle, since they resemble each other so 
much in their chemical and physical properties, and as it 
seems they have all the same origin. 
3. That in most cases it is indispensable, in making a 
correct chemical analysis, to treat the same substance both 
by the acids and the alkalis, since it has been demonstrated 
by expermments that a principle which the acids could not 
discover, may be ascertained by means of the alkalis. 
IV. Observations upon the emetic Property of the ligneous 
Part of Gray Ipecacuanha, and Analysis of that Root. 
By M. Henny, Professor of Chemistry in the School of 
Pharmacy, and Member of the Pharmaceutical Society of 
Paris*. 
Aone those authors who have written on the subject 
of ipecacuanha, we may reckon Adrien-Helvetius, Boulduc, 
Geoffroy, Neumann, Cartheuser, Lewis, and more recently 
Lassone jun. and Cornette, who, in the Memoirs of the, 
Royal Society of Medicine of the 31st of August 1779, have 
given analyses of this root, and have demonstrated that 
' § the ligneous part is very nearly as emetic as that which is 
separated from it.” 
Last of all, Murray, in the first volume of his Materia 
Medica (Apparatus Medicaminum), p. 804, relates, without 
asserting any thing positively, ‘ that, lately in France, (he 
quotes Lassone and Cornette,) it has been remarked that 
the ligneous part of this root was equally efficacious with 
the cortical part ; that it contained as much resin and ex- 
tract; and that an equal dose of it excites vomiting and al- 
lays dysentery.” 
In spite of the experiments of Lassone and Cornette, it 
seems that the lizneous part is never used, and apothecaries 
Are condemned who are not careful of rejecting it from their 
preparation of the ipecacuanha powder. 
Nobody, so far as I know, has repeated the experiments, 
* From Annales dé Chimie; tom. lvii. p. 28. 
announced 
