an anaesthetic, see ANAESTHESIA.
Chloroform may be given internally in doses of from one to five drops.
The _British Pharmacopoeia_ contains a watery solution--the _Aqua
Chloroformi_--which is useful in disguising the taste of nauseous drugs;
a liniment which consists of equal parts of camphor liniment and
chloroform, and is a useful counter-irritant; the _Spiritus Chloroformi_
(erroneously known as "chloric ether"), which is a useful anodyne in
doses of from five to forty drops; and the _Tinctura Chloroformi et
Morphinae Composita_, which is the equivalent of a proprietary drug
called chlorodyne. This tincture contains chloroform, morphine and
prussic acid, and must be used with the greatest care.

Externally chloroform is an antiseptic, a local anaesthetic if allowed
to evaporate, and a rubefacient, causing the vessels of the skin to
dilate, if rubbed in. Its action on the stomach is practically identical
with that of alcohol (q.v.), though in very much smaller doses. The uses
of chloroform which fall to be mentioned here are:--as a
counter-irritant; as a local anaesthetic for toothache due to caries, it
being applied on a cotton-wool plug which is inserted into the carious
cavity; as an antispasmodic in tetanus and hydrophobia; and as the best
and most immediate and effective antidote in cases of strychnine
poisoning.

CHLOROPHYLL (from Gr. [Greek: chloros], green, [Greek: phyllon], a
leaf), the green colouring matter of leaves. It is universally present
in growing vegetable cells. The pigment of leaves is a complex mixture
of substances; of these one is green, and to this the name, originally
given in 1817 by Pelletier and Caventou, is sometimes restricted;
xanthophyll (Gr. [Greek: xanthos], yellow) is dark brown; carotin is
copper-coloured. Chlorophyll is related chemically to the proteids; a
decomposition product, phylloporphyrin, being very closely related to
haematoporphyrin, which is a decomposition product of haemoglobin, the
red colouring matter of the blood. Chlorophyll is neutral in reaction,
insoluble in water, but soluble in alcohol, ether, &c, the solutions
exhibiting a green colour and a vivid red fluorescence. Magnesium is a
necessary constituent. (See S.B. Schryver, _Science Progress_, 1909, 3,
p. 425.)

CHLOROSIS (Gr. [Greek: chloros], pale green), the botanical term for
loss of colour in a plant-organ, a sign of disease; also in medicine, a
form of anaemia (see BLOOD: _Pathology_).