LAUGHTER, CONVULSIVE.—See HYSTERIA.
LAVENDER.—The fresh leaves and tops of the Larandula an aromatic shrub of the mint family (Labiatre). The oil of lavender is used as a perfume, and as an adjuvant in various remedies and hand lotions. A few drops of the spirit are sometimes given with some simple bitter in cases of indigestion with flatulence.
LEAD-POISONING.—Acute attacks of this form of poisoning sometimes occur as the result of the swallowing of sugar of lead or of white lead pigment. As a rule, however, it comes on insidiously, and pursues a chronic course. This is met with in persons who are engaged in handling the metal, or employed in establishments where the various products derived from lead are manufactured. The list includes smelters, lead-pipe workers, type-founders, compositors, potters and others who employ Iead-glazes, artists, painters and lacquerers who make use of the various lead-pigments, and furriers, hatters. and dyers who use lead sulphate for dyeing purposes. Lead-poisoning may be brought about also by eating or drinking from vessels which are incompletely glazed, by using food which has been preserved in cans soldered with lead, by drinking water which has been standing in lead-pipes, by using tea or chocolate which has been packed in lead-foil, by working on clothes which have been dyed with lead-pigments, and by the application of hair-dyes and face-paints which contain lead.
The acute form of lead-poisoning is marked by pains in the lower pertion of the abdomen, nausea, vomiting. bloody stools or constipation, vertigo and unconsciousness. This type often develops into the chronic form, the victims of which become emaciated and weak, with a pale, leaden com plexion (Plate XIV., 6). The gums are spongy, and at the dental margin there may be seen a slate-grey line, the so-called " lead-line." Among other symptoms, which may appear together or separately, may be mentioned severe colicky pains accompanied by obstinate constipation, nausea and vomiting, cutting pains in the limbs, temporary blindness, kidne•-disease, paralysis (usually of the arms), delirium, and convulsions.
It is only in the acute form of lead-poisoning that the laity can render any assistance to the patient. This should consist in the production of free vomiting, and in the administration of milk and eggs beaten out in water, and of a solution of Glauber's salt or Epsom salts (r to 2 table-spoonfuls in a pint of water). For the chronic form of poisoning the physician must be consulted ; but the patient should he immediately enjoined to give up the work which is the cause of the trouble. See also the article on OCCUPATION DISEASES.