166 
ON CATECHU. 
the orange colored solution with finely powdered carbonate 
of lead in small quantities at a time, and as long as its ad- 
dition occasions effervescence. Allow a slight excess of 
lead, sufficient to prevent chloride of barium forming a pre- 
cipitate with the filtered solution. At this point filter and 
evaporate in vacuo. The resulting tannin will be in the 
form of a transparent,. yellow, coherent mass, readily soluble 
in water, — but if evaporated in contact with the air, it will 
be of a deep red color, and not so completely soluble." 
This method enabled us to procure, allowing for some 
loss — about 40 per cent, of tannin. This, however, is be- 
lieved to be an undervaluation. * 
As an article of medicinal worth, we believe Gambir Ca- 
techu, by reason of its great astringency, and the amount of 
soluble extract furnished by it, to be equal, if not superior to 
a number of the astringent extracts ranked as Officinal Ca- 
techu, and consequently deserving a place in the shop of 
the apothecary. 
Augustine Duhamel,! 
John H. Ecky, > Committee 
Wm. Proctor, Jr. ) 
June, 1814. 
