WHELK.

521

bat it must not be allowed to dry during the exposure.

The colouring matter, which ig not soluble in water,

alcohol, oi' ether, may be rubbed up into a powder with

SUgar of milk. If givcn in largo doses to provers it

causes congestion of the womb, by stimulating that organ

too powerfully, together with pain in the breasts, and

a sense of sinking at the stomach as reHected from the

womb, also a frequent desiro to pass water, especially

by night, with mnch limpid watery urine. Whcrefore,

in small redueed dosos the triturated powder is of signal

remedial service for engorgements of the neck of the

womb, and for insipid diabetes with profuse urination

(but 110 sugar in the urine). Drs. Jacobson and

Blainville found uric aeid in these shell-tish as produced

by a sae or bag within them, similar to the organ which

secretes uric aeid in snails and other molluscs. It is,

supposed to be the iirst rudiment of a kidney. Dr.

Prout transformed uric aeid into a purple of great

beauty, which be termed "purpurate of ammonia," and

which Liebig has called " nnne.xide." The ancient

Tyrian purple, so magnificent of colour thal it was

worn only by kings and nobles, was the produet

of a marine whelk. Pliny supposed that the purple

liquor from which the dye was tnade had its discharge

from the mouth of the Murex, on which aecount the

fishermen were careful to catch it alive. Horace says

of those taken at Baia, "Murin' bajano melior"; and

Martial has written : —

" Non nigi vel ooeco madidä, vel murice tinetüVeste aites; et te sie dare vfcrba putas."

At Jaffa is found the Purpura paltda, a snail whichis sought by the native Christians 011 fast days.When this creature is punetured there issues a greenishliquid which changes to purple if exposed to the sun.