REPORT BY SURGEON-CAPTAIN J. F. EVANS.                          211

enough to mask or prevent the development of sensory-motor disturbance, with exception of
the rocking movements.

It was to this action of the drug that reference was made in the statement that the
"occurrence of symptoms of one kind either masked the occurrence or prevented the
development of those of another."

(c) Soporific or narcotic effects.—As already said, sleep production depends on the quantity
of the dose being influenced also by the individual idiosyncrasy: in some animals sleep was
easily and early induced as the result of the minimum dose; in others not so readily. The
duration and nature of the sleep depend on the quantity of the dose: it ranged from drowsiness
to slight narcotism. At the onset of sleep the cat often strived to maintain the sitting posture,
the head falling forwards now and again and the animal awaking with a start. As the
tendency deepened it usually lay down and went to sleep, the head gradually falling forwards
till the nose and front of the face rested on the ground.

Time of onset of symptoms.—Whatever their character might be, symptoms of the action
of the drug could generally be recognised within one hour or one hour and a half after its
administration. This statement applies only to the quantities given in this investigation, and
naturally will not bear too general application. In. my experiments the doses were always
small, and hence the use of the term minimal.

RECORD OF THE FIRST SERIES OF EXPERIMENTS WITH THE ALCOHOLIC EXTRACT
                                          OF THE STANDARD GANJA.

The quantity of the dose of the alcoholic extract usually given to small animals in physio-
logical investigations seems to have been about one or two grains. The first two doses adminis-
tered in this series of experiments were given without reference so much to the animal's body
weight as to serve as a guide by which subsequent experiments might be regulated.

Experiment No. 1.—Well-nourished male cat, weight 4lb 13½ oz.; a dose of the alcoholic
extract, weighing .25 grain, or about 1/135,000 part of the body weight, given at
12-22 P.M. Effect nil.

Experiment No. 2.—Male, weight of cat 4 lb 12 oz.; a dose of the extract weighing 5
grain, or 1/66,500 part of the body weight, given at 11-15 A.M. 12-45 P.M. Rocking
movements with slight weakness of the limbs, chiefly of the hind legs, on walking;
condition lasted about one hour.

As a dose equivalent to 1/66,500 of the body weight had induced definite symptoms, a similar
quantity was next administered to two other cats to test whether the experiment was
reliable:-

Experiment No. 3.—Yellow and white female cat, weight 7 lb 1 oz. .75 grain of the
extract, or a quantity equal to 1/65,000 of the body weight, administered at 11-45 P.M.
12-40 P.M. Nodding of head, drowsiness. 1 P.M., rocking movements, with occasional
slight tremor. 1-15 P.M., tendency to sleep more marked. Animal lying down asleep
with the nose and face resting on the ground. 2 P.M., effects of the drug begin-
ning to pass off.

Experiment No. 4.—Black and white cat, weight 3 lb 10¼ oz. .38 grain of extract, or a
quantity equivalent to 1/66,000 of the body weight, administered at 12-10 P.M. 1-15
P.M., rocking movements; cat is sitting up and displays occasional attacks of totter-
ing or irregular movements of the fore quarters and fore limbs, as though endeavour-
ing to save itself from falling forwards; is slightly drowsy. 2 P.M., cat appears
considerably distressed, is constantly mewing and suffering also from slight saliva-
tion. 3 P.M., beginning to recover, though still dull.

A dose equivalent to 1/66,000 of the body weight being able to cause easily recognisable
effects, the next step was to find out how far this dose could be diminished and yet definite
symptoms induced. In the four following experiments the quantity of the extract given to
each cat was equal to 1/75,000 part of its body weight:—

Experiment No. 5.—Weight of cat 6 lb 11½ oz. Dose of extract .63 grain at 1 P.M. 2-45
P.M., cat asleep with its nose on the ground, and though able to be disturbed by
any noise in its neighbourhood, yet it soon went to sleep again. It remained in
this sleepy state till 4 P.M. No rocking movements or tremor observed.

Experiment No. 6.—Weight of cat 3 lb 7¼ oz. Dose of extract .32 grain at 1-25 P.M.
2-50 P.M., displays symptoms of distress and discomfort with slight drowsiness; is
suffering also from slight salivation. 3 P.M., rocking movements. 4 P.M., the rocking
movements have lasted with intermission since 3 P.M., being interrupted by occasional
periods of sleep. 4-30 P.M., cat is still under the influence of the drug.

Experiment No. 7.—Weight of cat 3 lb 9½ oz. Dose of extract .34 grain at 1-45 P.M.
3 P.M., sleepy; displays rocking movements of the body from time to time. Effects
lasted for upwards of an hour.