40 Mr. Brande’s observations on an astringent 
Of the source of these bodies nothing is said, but on refer- 
ring to Du Halde, ( description de 1 ’ Empire de la Chine, &c. 
folio, Paris 1735, page 496'. 1 I found an account of a Chi- 
nese drug, entitled ou poey tse, and which appears to be the 
substance in question. Their formation is ascribed to small 
insects, and the general description of their exterior charac- 
ters agrees nearly with that I have given : they vary in 
size, from a small gall nut to a large chesnut. M. Geof- 
froy, in the Memoires de P Acad^mie Royale des Sciences, 
1724, has published a Paper entitled, “ Observations sur les 
vessies qui viennent aux Ormes, et sur une sorte d’excrois- 
sance a peu prbs pareille qui nous est apport£e de la Chine/' 
He conceives that the excrescences occasionally formed upon 
the elm are similar to those from China, but does not iden- 
tify the two by any experiments ; and indeed it would appear, 
from the account given by Du Halde, that the ou poey tse are 
obtained from a very different tree. These Chinese galls are 
likewise employed in medicine, and a full account of their 
various preparations are annexed to Du Halde’s observations. 
My first experiments were directed tfowards ascertaining 
the quantity of tannin which they contained, and which I have 
found considerably greater than that in any other vegetable 
astringent in common use. 
One hundred grains of the Chinese galls, freed from extra- 
neous matters, were reduced to a coarse powder, and infused 
in cold distilled water, till that fluid ceased to act upon the 
residuum. The infusion was of a very pale browm colour, 
and of a highly astringent flavour; it furnished a copious 
white precipitate with a solution of jelly, and became deep 
black upon the addition of the oxy-sulphate of iron. When 
