est is so delicate as to show the 1/25000 of a grain of
the alkaloid. A very minute quantity (1/5000 grain) in solution placed
on the skin of a frog after drying causes tetanic convulsions.

=Brucine.=--This alkaloid, found associated with strychnine, possesses
the same properties, though in a less powerful degree. Nitric acid gives
a blood-red colour, changed to purple with protochloride of tin.

XLV.--CANTHARIDES

=Cantharides.=--Spanish fly, or blistering beetle, is the basis of most
of the blistering preparations. It is sometimes taken as an
abortifacient or given as an aphrodisiac, but whether it has any such
action is open to question. It acts as an irritant to the kidneys and
bladder, and sometimes produces haaematuria and a good deal of temporary
discomfort.

_Symptoms._--Burning sensation in the throat and stomach, with
salivation, pain and difficulty in swallowing. Vomiting of mucus mixed
with blood. Tenesmus, diarrhoea, the motions containing blood and mucus.
Dysuria, with passage of small amounts of albuminous and bloody urine.
Peritonitis, high temperature, quick pulse, headache, loss of
sensibility, and convulsions.

_Post-Mortem._--Gastro-intestinal mucous membrane inflamed, with
gangrenous patches. Genito-urinary tract inflamed. Acute nephritis.

_Treatment._--An emetic of apomorphine; demulcent drinks, such as
barley-water, white of egg and water, linseed-tea and gruel (but not
oils), with a hypodermic injection of morphine to allay pain.

_Tests._--The vomited matter often contains shining particles of the
powder. The urine will probably be albuminous.

XLVI.--ABORTIFACIENTS

Emmenagogues are remedies which have the property of exciting the
catamenial flow; ecbolics, or abortives, are drugs which excite
contraction of the uterus, and are supposed to have the power of
expelling its contents. The vegetable substances commonly reputed to be
abortives are ergot, savin, aloes (Hierapicra), digitalis, colocynth,
pennyroyal, and nutmeg; but _there is no evidence to show that any drug
possesses this property_. Lead in some parts of the country is a popular
abortifacient. A medicine may be an emmenagogue without being an
ecbolic. Permanganate of potassium and binoxide of manganese are
valuable remedies for amenorrhoea, but will not produce abortion. The
vegetable substances frequently used as abortives are savin and ergot.

=Savin= (_Juniperus Sabina_).--Leaves and tops of the plant y