64 
COLD WATER AS A SOLVENT OF DRUGS. 
quantity of oxide contained in it varies according to its age and 
the mode of preparation. 
4. Hence a more uniform and effective preparation can be made 
from the pure protoxide. 
5. Vapors of mercury first produce inflammation of the lungs, 
subsequently oxidation and absorption take place, and the symp- 
toms of mercurialism commence. — Jour. fur. Prakt. Chem. No. 9, 
1850. — London Chemical Gazette, Sept. 1st, 1850. 
ON COLD WATER AS A SOLVENT OF THE ACTIVE PRINCIPLES 
OF DRUGS. 
By Mr. Richard Battley. 
In the preparation of medicines, there are a few points to which 
I have especially directed my attention, and to which I shall take 
this opportunity of inviting your attention, believing that the con- 
clusions to which I have come, suggest the general introduction of 
a new form of medicine, and of an important alteration and im- 
provement in one now in common use. 
1. The superiority of cold to boiling water as a menstruum for 
nearly all vegetable substances. 
2. The quantity of water to be employed. 
3. The extent to which the evaporation of the product can be 
safely and advantageously carried. 
1. The object of the various menstrua employed, as hot and 
cold water, spirit, ether, vinegar, &c, is of course to dissolve the 
active principles with as little as possible of the inert constituents, 
which not only do not improve, but often greatly impair the pro- 
perties of the medicine. I believe I have employed cold distilled 
water for this purpose far more largely than has been customary 
in this country or elsewhere ; but the Edinburgh and Paris Phar- 
macopoeias have, in their last editions, adopted it to a much greater 
extent than formerly. The advantages of cold water, that is, 
of water at the ordinary temperature of the laboratory, say 60 or 
65, are, first, that it dissolves from the tissue of plants, in two or 
three macerations, all or nearly all the active principles soluble 
in boiling water, spirit, or ether, taking up even resin abundantly 
