408 Rumex Crispus — Yellow Dock. 
There is a crystalline principle, in small quantity, in the root 
which conducts itself somewhat like gallic acid. 1 have not yet 
examined it sufficiently to satisfy myself whether it is this or 
some other body. It shows itself in small acicular crystals, 
taking often a stellated arrangement. They are readily soluble 
in water, less readily soluble in absolute alcohol, and sparingly 
soluble in ether. They are found in the water and spirit extracts, 
from which they can be separated in a tolerably pure state by 
sulphuric ether, which slowly dissolves the crystals without 
taking up much of the amorphous extractive matter. The crys- 
tals dissolved in sulphuric acid and the solution raised to a tem- 
perature of about 200° is changed to a light amber color. The 
examination of this body will be resumed as soon as there is time 
to take it up. 
Riegel found in the root of the Rumex obtusifolius a peculiar 
principle which he called rmnicin, and which bears a close re- 
semblance to rhabarbarin, one of the active principles of rhubarb. 
The crystals observed in the R. crispus, may be identical with 
the rumicin of the R. obtusifolius. 
The root also contains a small amount of sufjar and a slig-ht 
quantity of an oily resinous body. 
Uses and Medical Properties. The leaves are sometimes eaten 
for greens. They are somewhat laxative, and form an excellent 
diet in scorbutic complaints. The roots contain a yellow dye, 
and are said to be sometimes used in coloring. The dye on ex- 
posure to the atmosphere for some time, changes to a reddish yel- 
low color. 
Though this species is not officinal, yet it has enjoyed at different 
times considerable reputation as a medicine. Its medical pro- 
perties are those of an astringent and mild tonic. In this 
respect it has some resemblance to rhubarb. It is supposed to 
possess an alterative property* and has been employed in decoc- 
tion and ointment in scorbutic disorders and cutaneous eruptions, 
and has attracted some attention in the treatment of itch. The 
powdered root has been recommended as a dentifrice in cases of 
spongy gums. Recently it has been employed quite extensively 
in syrups and patent medicines. 
It yields its active properties to water and alcohol. The 
infusion or decoction is of a light yellow, and the tincture of a 
dark yellow color, (the latter takes up nearly all the coloring 
matter,) with an odor of the root and an excessively pungent bit- 
ter taste. It requires several fresh additions of water or alcohol, 
before the active properties can all be abstracted. The residue 
after sufficient maceration is inodorous, and almost tasteless. In 
several trials of this kind, it w^as found necessary to add water or 
alcohol from four to five times, keeping the whole after each ad- 
