356 - RHAMNEA. 
the dye under the name of Popli, and places it amongst the 
_ forest products of Mysore. (ii. 305.) 
Description.—The Ventilago is a large scandent shrub, 
and reaches to the top of the highest trees in the forests 
where it grows. ‘The leaves are ovate, acuminate, coriaceous — 
and shining, and the flowers are in slender spikes. The fruit 
- is samaroid, from 14 to 2 inches long, and 2 inch broad ; the 
nut is about the size of a pea, girt at the base by the remains 
of the calyx forming a disc. The roots are from 4 to 1 inch 
in diameter, and rough ‘with reddish loose scales. The drug 
consists of the root bark in scales made up of numerous papy- 
raceous layers of a deep reddish brown colour, and in some 
of the older pieces, with a metallic lustre. Wembaédam bark 
gives up a red colour to water, and an intensé reddish brown | 
colour to rectified spirit; by being heated together the colour- 
ing matter is communicated to certain fats and fixed oils, and 
it is taken up by volatile oils even in the cold. 
Chemical composition.—By treating the drug with water . 
a liquor is obtained of red colour and slight acid reaction, 
giving violet red precipitates with lead acetate, calcium and 
barium hydrates, a rose-tinted lake with alum and potassium 
carbonate, and muddy mixtures with ferrous and ferric salts. 
The alcoholic solution is more acid in reaction, and does not 
_ precipitate with alcoholic lead acetate; the colour is removed 
~ from solution by means of animal charcoal, but not by heating 
with zine dust. Evaporated carefully to dryness no crystals 
were observed, and the red mass re-dissolved in chloroform, 
_ benzol and carbon disulphide, and in alkaline solutions with a 
magenta hue, which was discharged by acids. This colouring 
matter is of an acid nature, and is probably one of the deriva- 
tives of anthracene, 
Commerce.—Vembidam bark is collected extensively on the 
northern slopes of the Nilgiris. In the Annual Report of the 
Madras Forest Department for 1887-88, it appears that 3 tons 
were collected, which realized a revenue of Rs. 62, the value of 
_ the permits. During the year 1888-9, 41 maund of Ist class 
