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936 experiments. The glucose obtained from the decomposition was inactive towards polarized light. An infusion or tincture of the root boiled with diluted acid gradually loses its bitterness, and a large increase in the sugar is detected by Fehling's solution. Picrorhizetin is a red-brown, brittle, resinous, tasteless body soluble in aqueous alkalies. It is insoluble in water, and its solution in alcohol is precipitated by ether. By heating with strong sulphuric acid Or when being burnt it evolves an odour of benzoin.

The wax after bleaching, and purifying by recrystallization from hot alcohol, had a melting point of 51° C. The organic acid separated by lead was red-coloured and gave a greenish colour with ferric salts. No tannic acid was present. Some picrorhizetin was naturally formed in the drug, and existed in a much smaller proportion in the freshly dried rhizome. After removing the bitter principle by continued percolation with alcohol, the marc was dried and exhausted with water, the dark red-brown solution was evaporated to dryness, and .2 gram of the residue was found to act as a decided purge. The aqueous extract treated with four volumes of alcohol afforded precipitates containing 14.5 and 15.3 per cent, of mineral matter, and with six volumes a precipitate was obtained with 10 8 per cent, of ash. We rely upon the physiological action of this extract in considering cathartic acid to be a constituent." Pharmacographia Indica, Vol. VII, pp. 12-13.

Dr. Lai Mohan Ghoshal concludes his thesis on Picrorhiza Kurrooa, in Food and Drugs for January, 1912 as follows : —

1. The drug Picrorrhiza Kurrooa has got a bitter principle named picrorrhizin a glucoside, mainly.

2. Its action is due to its bitter principle.

3. It has got no poisonous action.

4. It increases the gastric secretion and thereby acts as a stomachic and bitter tonic.

5. It diminishes the force of the heart beat and hence may be used in febrile cases, beneficial effect being due to the reduction of blood pressure.

6. It has a mild laxative action due to the presence of cathartic acid.

Habitat : — N.-W. India, from the plains of the Punjab to Western Tibet, and from Kashmir to Bhutan. Bengal, the Khasia Mts. and Assam, the Deccan Peninsula, in the Concan only.

A perennial, glabrous, rarely pubescent erect, succulent herb. Stem hollow, creeping below, from 6-18in, high and from the thickness of a sparrow's quill to that of the middle finger. Leaves 2-6 by ⅓-⅔in., sessile (stem-clasping) or lowest petioled. oblong lanceolate or linear-oblong, entire or serrate, base, usually cordate. Flowers pale purple, pink or white, 1/6-⅓in.