t contact. The ends of the bones are thus exposed, and their
medullary cavities exposed to infection. As a result we get in them the
changes we have already described under Ostitis.

_Treatment_--_(a) Preventive_.--Seeing that many of these cases have their
starting-point in stabs or penetrating wounds of the sole, we shall be
concerned first with a consideration of the correct treatment to be adopted
when we know the wound to have reached the articulation.

Only too frequently the treatment practised is that of poulticing. In other
portions of this work we have pointed out the advantages that a continued
antiseptic bathing has over the application of a poultice, the greater
readiness with which the solution comes into contact with the deeper parts
of the wound, and the far greater chance there is of maintaining water in
an antiseptic condition than there is of keeping a poultice in the same
state. There is no doubt, that in this case also, the cold or warm
antiseptic bath is to be preferred to the poultice. It is questionable,
however, whether even the bath is sufficient for our purpose here. We have
in this case a deep punctured wound, and a wound that in every probability
is infected with the organisms of pus or of putrefaction. It is a wound,
moreover, which is likely to impede the thorough access to it of the
solution in which the foot is fomented, on account of the flakes of
coagulated fibrin which fill it.

The most rational treatment, therefore, if we get to the case early enough,
is to irrigate the wound freely with a solution of carbolic acid in water
(1 in 20), or with a solution of perchloride of mercury (1 in 1,000),
injected by means of a glass syringe, or the pattern of syringe devised for
quittor. This injecting should be done thoroughly, and by that we mean that
several syringefuls of the solution should be injected, the joint after
each injection being manipulated so as to distribute the solution as far as
possible over it. When this is done the opening in the sole may be plugged
with a little perchloride of mercury, or, better still, with a little piece
of tow saturated with a concentrated solution of perchloride of mercury
or a solution of iodoform in alcohol and an antiseptic pad of tow or lint
placed over all. The foot should then be bandaged and encased in a boot or
sacking protective. The bandage should be removed daily and the antiseptic
pad changed. At each visit the animal's condition must be