CELATINIZ ATION OF TINCTURE OF KINO. 261 
again into metapectic acid by the prolonged action of an al- 
kali. Tannic acid, also, when in solution, speedily undergoes 
a change, even from the action of the atmospheric air. We 
might, therefore, easily account for the conversion of pectin 
into pectic acid, supposing the former to be present in the 
kino. 
But it does not appear that Botany Bay kino is now intro- 
duced into our market. Dr. A. T. Thomson says, he has been 
informed "that little of it has been brought to this country 
since 1802." He states that the kino generally met with in 
the shops, is that imported from the East Indies, and is an 
extract formed by inspissating a decoction of the branches 
and twigs of the Nauclea Gambir, a plant belonging to the 
natural order Cinchonacese. 
East Indian kino has been examined by Vauquelin, who 
gives the following as the result of his analysis: Tannin 
and peculiar extractive matter 75; red gum 24; insoluble 
matter 1. Now we have no mention here of the existence 
of pectin in this species of kino; and this fact, taken in con- 
nexion with that of the tincture becoming gelatinous when 
made with rectified spirit, would naturally tend to the con- 
clusion, that the property under consideration must be 
due to some other cause than that to which it has been as- 
signed. 
The following experiments were undertaken with the view 
of further investigating this subject. A sample of tincture of 
kino was obtained, which was almost completely gelatinized, 
a small portion only of fluid floating on the surface. This 
fluid was separated by repeatedly washing the gelatinous 
mass with cold water. The washings slightly reddened lit- 
mus paper, and on being tested with gelatine afforded a pre- 
cipitate indicating the presence of tannic acid. The quantity 
of tannin detected in this way was very small. The jelly, 
after being purified by washing, was perfectly insipid, and 
insoluble in cold water, in alcohol, and in ether. This sub- 
stance was dried and pulverized, and then treated with boil- 
ing water, which took up a very small proportion, and formed 
