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wanting abundant nostrums for this purpose among the numerous 
professors of horse physic. At the natural annual period of their 
transformation they come away readily enough of themselves ; 
and if it happens at the time that any medicine has been exhibited, 
it is considered as proof enough of its efficacy, and mistaken for 
the consequence of it; so easy is it to draw wrong conclusions. 
Neither opium or tobacco given for several days have any effect 
upon them, as I have witnessed by opening the stomach after the 
death of such, and finding them lively and well. We can, it is 
true, force the poison down the horse’s throat, but we cannot 
afterwards get it into the throat of the worm, who is placed in his 
own element, and can refuse the food that does not suit him. 
Truly is it therefore difficult to destroy them by means of poisons 
thrown into the stomach. 
Oils, to close the pores of respiration, and thus kill them, was 
a favourite suggestion of the last age for worms of all kinds, and 
it was thought must infallibly bill them : nevertheless it did not. 
These oils probably in the stomach are soon reduced to a soap, 
and digested ; how much less then could it affect worms situated 
in the intestines. 
The wisest measure for securing animals from their effects is to 
prevent their propagation or access, and their habits expose to us 
an effectual mode of doing this. The eggs of the Oestrus Equi, 
which are very conspicuous on the knee, the mane, and the sides 
of the horse, may be washed off by a brush and warm water, or 
still more effectually removed by a pair of scissars. The same 
may be done for the Hagmorrhoidalis from the lips and beard. 
The other species being smaller, more rare, and probably less 
troublesome, require therefore less our. consideration. 
In respect to the Hasmorrhoidalis also, where horses have been 
much out at grass the preceding year, they should occasionally in 
the warm months of the next summer be examined for them, when 
they will be found, as we have already stated, hanging to the 
