192 
ON THERAPEUTICS. 
crutches, or, at best, prevent his performing a decimal part 
of the work in proportion to what will be required of a horse 
under similar circumstances. 
In discussing the effects of counter-irritation in cases of 
exostosis, splint, or spavin, or deposit upon the edges of 
articular surfaces, fibrous deposits, sprains of tendon and 
ligament, relaxation of ligament or bursal enlargements, and 
various sub-acute or chronic inflammations, we may arrange 
the means under the three heads of " Blister, 0 “ Seton,” and 
“ Firing.” 
Blisters are employed in these cases for the purpose of 
removing any inflammation which may occasion lameness, or 
with the intention of diminishing a deposit. Their influence 
on inflammation we have already explained in reference to 
cases of internal disease. In the cases we are now discuss¬ 
ing, the effect upon the circulation in the diseased part will 
be more marked in consequence of its proximity to the sur¬ 
face where the counter-irritant is applied. We cannot 
assume for a moment that the blood is diverted from the 
seat of disease by the action of an irritant upon the same 
spot; but undoubtedly there is a more energetic circulation 
through the whole of the surrounding vessels during the 
action, which probably removes the congestion, while the 
nerves receive a new and more healthy stimulus. Sometimes 
the deposits are lessened after the primary action has sub¬ 
sided, but not by any means usually. Iodine compounds, 
as the biniodide of mercury or iodide of potassium, have a 
more decided power in this respect than any other irritants, 
particularly when used in small quantity, and applied fre¬ 
quently. Blisters of any other kind, setons, and the cautery, 
certainly very often increase the amount of deposit, whether 
of bone or fibrous tissue. 
Blisters are also applied in cases of sprained tendons or 
ligaments or enlarged bursae. The benefits resulting are due 
to the rest which the application necessitates, and to the 
subsequent support from the thickening of the integument, 
which continues for a long time after a blister has been used. 
The good effects are commonly temporary; and for this 
reason blisters are inferior to the cautery in the treatment of 
these diseases. 
Setons are more continuous in their action than any forn7 
of blister. Whether as “ issues,” “rowels,” or in the com. 
mon form of seton, they occasion inflammation and its results, 
effusion and ultimately suppuration. As the formation of pus 
is an exhausting process, consisting in oxidation and ex¬ 
cretion of the colourless corpuscles, it will never be advisable 
