sed in America by the
Coffenite practitioners, and a valuable remedy for asthma.

_Symptoms._--Nausea, vomiting, giddiness, cold sweats, prostration.
Headache, giddiness, tremors, insensibility, and convulsions.

XLI.--HYDROCYANIC ACID

=Prussic Acid= is the most active of poisons. The diluted hydrocyanic
acid of the Pharmacopoeia contains 2 per cent. of hydrocyanic acid,
Scheele's 4 per cent. It is a colourless liquid, feebly acid, with
odour of bitter almonds.

=Cyanide of Potassium= is largely used in photography and in
electro-plating, and is also poisonous. It often contains undecomposed
carbonate of potassium, which may act as a corrosive poison and cause
erosion of the mucous membranes of the lips, mouth, and stomach.

=Oil of Bitter Almonds=, used as a flavouring agent, may contain (when
improperly prepared) from 5 to 15 per cent. of the anhydrous acid.

_Symptoms._--The symptoms usually come on in a few seconds, and are of
the shortest possible duration. There is a sudden gasp for breath,
possibly a loud cry, and the patient drops down dead. If the fatal
termination is prolonged for a few minutes, the symptoms are intense
giddiness, pallor of the skin, dilatation of the pupils, laboured and
irregular breathing, small and frequent pulse, followed by
insensibility. There may be convulsions or tetanic spasms, with
evacuation of urine and faeces. Death results from paralysis of the
central nervous system, but artificial respiration is useless, as the
drug promptly arrests the heart's action. It also kills the protoplasm
of the red blood-corpuscles, rendering them useless as oxygen-carriers.

_Post-Mortem Appearances._--Skin livid, pale, or violet, with bright red
patches on the dependent parts. The gastro-intestinal mucous membrane is
bright red in colour, owing to the presence of cyanmethaemoglobin. Hands
clenched, nails blue, jaws fixed, froth about mouth. Eyes prominent and
glistening, odour of acid from body, venous system gorged.

_Treatment._--Empty the stomach by the tube at once, and wash it out
with a solution of sodium thiosulphate. Strong ammonia to the nostrils.
Stimulants freely--brandy, chloric ether, ammonia, sal volatile _ad
libitum_. If patient cannot swallow, inject hypodermically either brandy
or ether. Hypodermic injection of 1/50 grain atropine. Douche to the
face, alternately hot and cold. Death commonly occurs so rapidly that
there is no time for treatment.

_Fatal Dose (Sma