at importance in treating all
wounds of the foot. There is a great temptation, on account of the known
excessive liability of the parts to septic infection, to use an antiseptic
solution unduly strong. What must be remembered is that used _too_ strong
they themselves give rise to dead tissue, or to impermeable layers
consisting of compounds of the discharges with themselves, and so create
substances that prove a source of irritation and subsequent trouble.

_The Potential Cautery_.--This is employed in the treatment of sub-horny
quittor, either in the solid form (in sticks, in lumps, or in the powder),
or in the liquid form, when it is injected with a quittor syringe.

In the former method such drugs as perchloride of mercury in the lump, or
nitrate of silver, chloride of zinc, and caustic potash or soda in the
stick, are introduced into each of the sinuses present. This is done by
means of a director or a probe.

A better method, however, when the dressing lends itself to the purpose, is
to use it in the form of a powder, wrapped in the form of small cubes
in extremely thin paper, such, for instance, as is used for rolling
cigarettes. It is then conveniently inserted into each fistula. Introduced
in this more finely divided form the drug is, perhaps, a little more active
in bringing about the desired result.

This method of 'plugging,' although practised by many, we cannot recommend
in preference to the use of the hot iron or of liquid injections. Our
reasons are these: the action of the drug is a protracted one. Almost
immediately after its introduction into the fistula there is formed about
it an almost impermeable layer of a metallic albuminate, which effectively
prevents further rapid action of the caustic. In addition to thus
preventing further action of the dressing, this combination of the tissue
albumin with the metal of the salt, together with much necrotic tissue that
it has caused, is extremely hard to remove from the healthy tissues. This
we explain by pointing out that the action of the caustic, prolonged as
it is, sets up a tissue reaction which partakes largely of the type of a
chronic rather than an acute inflammation. With a chronic inflammation
there is sooner a tendency to the production of fibrous tissue (and thus
the firmer attachment of the necrosed portions) rather than an active
phagocytosis and the casting-off of a slough. Again, careful though we may
be with the probe, it is extremely diffic