ON DRUG-GRINDING. 19 
i 
alone for a long time, while at their work. In order to 
avoid this drowsiness while at their work, many* labourers 
attach an onion cut in two in front of them, and carry 
another with them, which they smell occasionally. This is 
found to protect them from any such inconvenience. 
From a single capsule they obtain &grai?i of matter; one 
measure of ground produces at most 3,750 drackmes, (Fr.) 
orl5 tchekis, 250 drachmes (Fr.) being estimated to our 
tchekis, though sometimes they are so unfortunate as to ga- 
ther only one tcheki from that space. 
After the extraction of the opium, the capsules are 
allowed to remain, in order to procure from them the seed. 
After a time they are cut off from the stalk and spread out 
upon the ground to dry ; when a suitable occasion arrives, 
they are spread out and stamped upon till thoroughly broken 
up, the whole being then transferred to a large basin filled 
with water; the rinds float on the surface, and are thus sepa- 
rated from the seed, which are collected in the bottom of the 
vessel and preserved. 
When the different species are mixed, and it is designed 
to separate them, it is necessary to puncture each capsule 
and ascertain the colour of the seed, and to divide them into 
separate portions before proceeding as above. 
ART. V.— ON DRUG-GRINDING. 
By Mr. Theophilus Redwood, 
Professor of Chemistry and Pharmacy to the Pharmaceutical Society. 
A large proportion of the solid substances employed in 
medicine, are submitted to certain processes by which they 
are reduced to powder, either as a preparatory step to sub- 
sequent pharmaceutical processes, or to fit them for admin- 
istration in the solid state. It is, therefore, an interesting 
