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OBSERVATIONS ON LEECHES. 
The treatment of leeches in the manner above described 
would lead, especially in large hospitals, to a considerable 
saving of expense. It need scarcely be mentioned that this 
plan cannot be adopted with those which have been applied 
to individuals suffering from contagious diseases. For such 
cases I may however direct attention to the fact, that when 
a portion of the foot of the leech is cut off while it is suck- 
ing, the leech then, instead of removing as usual 1 or 1§ oz- 
of blood, will take 3, 4, and even 5 oz. Should this be con- 
firmed, it will be possible to effect with one leech what other- 
wise would require two or three. 
With the constantly-increasing rarity and expense of the 
officinal leech, it is certainly desirable to draw more atten- 
tion to the horse-leech, Him do vorax, which is met with in 
many districts in considerable numbers. 
I have also made some experiments with these leeches, 
and have generally obtained similar results. Thirty speci- 
mens of ordinary size were employed, and I never observed 
any serious inflammatory wounds, or other ill consequences, 
result from their use. Even were they not to be employed 
on the more tender parts of the body, they might still be 
made use of in very many cases. 
I will now add some observations on the preservation and 
breeding of the leech, and also a word or two respecting the 
difficulty which sometimes occurs of bringing the leeches to 
bite. 
With respect to the preservation of leeches, I have fre- 
quently had occasion to keep them, even in very considerable 
quantities, for half a year and more in pure water, in which 
were placed some plants of Calamus, renewing the water 
every eight days in summer, and every three or four weeks 
in winter. This plan I consider to be the best, especially 
with small quantities. 
I cannot advise the use of loam, turf, or patches of grass 
intermingled with roots of Calamus, which are frequently 
had recourse to, as I have learned from experience that it is 
