586 SAXIFRAGACEZE. 
diuretic in doses of 15 grains. It is also said to be an antidote 
to opium, to have tonic properties, and to be useful as an 
astringent in diarrhoea and pulmonary affections. Sometimes 
it is applied externally as an astringent. In Sind it is rubbed 
down with honey into a paste, which is applied to the gums of 
children when teething ; if used freely in this way it may do 
harm by confining the bowels too much. 
Description.—Tho- rhizome occurs in pieces 1 to 2 
inches long, and about half to one inch in diameter. The 
external surface is brown, wrinkled and scaly, and bears nume- 
rous scars of rootlets, and circular markings. The substance is 
dense and hard, with a reddish colour. The rhizome appears 
to have been cut up before drying. The red colour of thé 
sections is only external, as a fresh cut shows the interior to 
be much lighter, or almost white. Under the microscope there 
are seen numerous conglomerate crystals and ovoid starch cells. 
The taste is slightly astringent, and the odour similar to that 
of tan, but more aromatic. 
Chemical composition.—The ethereal extract of the finely 
powdered rhizome was of a pale brown colour, somewhat crys- 
talline, and contained the peculiar odorous principle of the drug. | 
The aqueous solution of this extract gave inky mixtures with 
ferric and ferrous salts, and precipitated gelatine solution. 
The mixture of tannic and gallic acids was shaken up in solution 
with pure ether, and the supernatant liquor afforded the gallic 
acid ina pure condition, known by its reactions with strong 
sulphuric acid and alkalies, and by mixing clear with gelatine. 
Alcohol removed from the residue of this extract an odorous 
_ body of soft fatty consistence, and the remainder of the extract 
was a wax, melting about 48° C. The wax was insoluble in 
cold alcohol, but almost entirely dissolved on boiling, sepa- 
rating into a mass of crystalline plates when cooled, not wholly — 
‘dissolved after prolonged boiling with alcoholic potash, not 
_ soluble in cold or hot sulphuric acid; in the’ latter it first 
urned red, then melted and blackened ; nitric acid decomposed 
nto a yellow brittle resin. Ss Berens ee 
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