532 
Facts and Observations. 
ON THE ACTION OF HYDROCYANIC ACID IN THE HORSE. 
To the Editors of the c Veterinarian? 
Dear Sirs, — At page 277 of your valuable Journal there 
is an account given of the action of hydrocyanic acid on 
different animals. Having been recently called upon to 
attend an aged horse, which they said had fallen down and 
could not rise, I found, upon examination, that he had 
fractured two of his ribs. The owner not wishing the trouble 
or expense of keeping him, desired me to destroy him with 
prussic acid. I accordingly gave him nearly an ounce of 
Scheele’s strength acid, and at first it appeared to be having the 
desired effect, but after a few struggles and great difficulty of 
breathing, its action gradually subsided, and it had no further 
influence. I wish to know whether it has been ever given to 
horses before with a view to destroy life. 
I remain, yours respectfully, 
John Brown. 
23, Whitepriars Street. 
[Occasionally hydrocyanic or prussic acid has been resorted 
to for this purpose. Two ounces being considered the average 
quantity necessary to destroy life in the horse. But it is not 
an agent that can be relied on. Its action would appear to 
be very variable on different animals ; and this not dependent 
on its strength so much as the susceptibility of the animal 
to be influenced by it. 
The late Professor Coleman w’as anxious to ascertain its 
effects on the horse, and a number of experiments were 
instituted by him, which were superintended by us, and of 
them the following rough notes were at the time recorded. 
The acid employed was that designated Scheele’s strength. 
Gradually increased, doses were at first given to an aged 
animal until two drachms twice a day were administered 
without any apparent action supervening. A few daj^s after- 
wards two drachms were administered at once in four ounces 
of water. In five minutes after its exhibition the pulse had 
risen to 60, the respiration became hurried, and tetanic 
twitchings of the muscles generally showed themselves. 
These effects, however, very soon passed off. 
On the following day the same dose was again administered, 
