rmates, led Liebreich to the conjecture that a similar decomposition
might be produced in the blood; and hence his introduction of the
drug, in 1869, as an anaesthetic and hypnotic. It is now known,
however, that the drug circulates in the blood unchanged, and is
excreted in the form of urochloralic acid. The dose is from five to
twenty grains or somewhat more, and it is often given in the form of
the pharmacopoeial _Syrupus Chloral_, which contains ten grains of
chloral hydrate to the fluid drachm. Chloral hydrate must be well
diluted when given by the mouth, as otherwise it may cause
considerable gastro-intestinal irritation. In large doses chloral
hydrate is a depressant to the circulation and the respiration, and
also lowers the temperature. In the above doses the drug is a powerful
and safe hypnotic, acting directly on the brain, and producing no
preliminary stage of excitement. Very soon--perhaps twenty
minutes--after taking such a dose, the patient falls into a sleep
which lasts several hours, and is not distinguishable from natural
sleep. When he wakes, it is without disagreeable after-symptoms, but
with a feeling of natural refreshment. The pupils are always
contracted under its influence, except in large doses. There is also
rapidly induced a depression of the anterior horns of grey matter in
the spinal cord, and as the symptoms of strychnine poisoning are due
to violent stimulation of these areas, chloral hydrate is a valuable
antidote in such cases. It should not be hypodermically injected. Its
disadvantages are that it is powerless when there is pain, resembling
in this feature nearly all hypnotics except opium (morphine) and
hyoscin. Its action on the gastro-intestinal canal and on the
respiratory and circulatory systems renders its use inadvisable when
disease of these organs is present. Its action on the spinal cord has
been employed with success in cases of tetanus, whooping-cough,
urinary incontinence, and strychnine poisoning. In the latter case
twenty grains in "normal saline" solution may be directly injected
into a subcutaneous vein, but not into the subcutaneous tissues.

_Toxicology._--In cases of acute poisoning by chloral hydrate, the
symptoms may be summarized as those of profound coma. The treatment is
to give a stimulant emetic such as mustard; to keep up the temperature
by hot bottles, &c.; to prevent or disturb the patien