316 
ON HYDROCYANIC ACID. 
fatal injury to the base of the brain, that I advised the owner, as 
the most charitable course, to destroy the animal, to which he con- 
sented, and, being in a public stable, it was objected to have him 
put to death so as to cause the flow of much blood. I therefore 
proposed to administer hydrocyanic acid, and proceeded by inject- 
ing into the jugular vein six drachms of acid, the effect of which 
was to restore the depressed vital powers. He gained both sensi- 
bility and power in the hinder extremities; the eye lost its coma- 
tose appearance, with contractility of the pupils ; the pulse, which 
had been almost imperceptible, rose ; the breathing increased, but 
not very much beyond natural respiration. These symptoms re- 
mained the same for half an hour, when it being imperative to put 
an end to the animal’s life, and not liking to be foiled, I gave one 
ounce more by the mouth. This, certainly, increased the effect, 
but it did not destroy life. After wasting about twenty minutes 
longer, I gave a third ounce, which at the end of another half-hour 
did not produce death, and there was every probability of the ani- 
mal recovering from the poison. I was at last obliged to end the 
scene by dividing the spinal cord between the first and second 
cervical vertebrse. 
Thus this little animal took two ounces and three quarters in one 
hour and twenty minutes of the most subtle poison known without 
destroying life, and with every probability of recovering from its 
effects. On the following morning 1 carefully examined the brain, 
and found, as the symptoms clearly indicated, extravasation at the 
base of the cerebrum and medulla oblongata. I made a prepara- 
tion of the brain, which I still have, and which shews very per- 
fectly the extent of the extravasation. 
The second case was one of a different kind. A very fine light 
cart-horse had been under my treatment for a long period for dis- 
ease of the nervous system, believed to have its seat in the spinal 
cord, about the lower cervical or upper dorsal portion, and also 
shewing, before he was destroyed, strong symptoms of the disease 
having affected the brain. The case being hopeless, it was deemed 
advisable to destroy the horse ; and as an experiment, and in the 
presence of my friend Mr. William Percivall and my father and 
brother, half an ounce of hydrocyanic acid was thrown into the 
jugular vein. The symptoms were as those described in the first 
instances; but from the smallness of the dose, and it being evi- 
dent to me that it was not sufficient, at the end of eight minutes I 
poured into the expanded nostril two drachms more of the acid. 
This had a very marked effect, and life had ceased in about twelve 
minutes. 
The autopsy shewed disease of the pia mater at the apex of 
both lobes of the cerebrum, of the superior part of the medulla 
