_Ten Minutes_.--Lameness had almost disappeared; so much so, that the
opinion as to navicular disease was confirmed, and neurectomy was
performed. Immediately after this operation there was no lameness whatever.

The same author also reports numerous cases among horses and cattle, dogs
and cats, pointing out the toxic properties of the drug. The symptoms
following an overdose are interesting enough to relate here, and I select
the following case of Professor Hobday's as being fairly typical:[A]

[Footnote A: _Loc. cit_.]

CASE IV.--Cart gelding. Free clinique; navicular disease. Injected
subcutaneously over the metacarpal nerves on each side 6 grains of cocaine
in aqueous solution. During the operation the animal manifested no signs
of pain whatever, not even when the nerve was cut. This animal received
altogether 12 grains of cocaine (3 grains were given on either side first,
then fifteen minutes afterwards the same dose repeated). The effect was
manifested on the system in ten minutes after the second injection by
clonic spasms of the muscles of the limbs (the legs being involuntarily
jerked backwards and forwards at intervals of about twenty seconds), which
materially interfered with the performance of the operation. The animal was
also continually moving the jaws, and was very sensitive to sounds, moving
the ears backwards and forwards. This hyperæsthesia, as evinced by the
movement of the ears, lasted for some considerable time after the animal
had been allowed to get up.

Cocaine hydrochlorate solutions, if intended to be kept for any length of
time, should have added to them when freshly made 1/200 part of boric acid
in order to preserve them. Even then they are liable to spoil, and should,