A New Supplement...: L. Lac. Lac virginis. Laccic acid. Laccin. Lacquers. Lamp black. Lardner's prepared charcoal. Litmus; lacmus. Luteoline.

A New Supplement to the latest Pharmacopoeias of London, Edinburgh, Dublin, and Paris, Forming A Complete Dispendatory, Conspectus, and Dictionary of Medical Chemistry, Giving All the Old and New Names, Including the New French and American Medicines, and Poisons; with Symptoms, Treatment, and Tests; as Well As Herbs, Drugs, Compounds, Veterinary Drugs, With the Pharmacopoia of the Vetenary College, Nostrums, Patent Medicines, Perfumery, Paints, Varnishes, And similar articles kept in the Shops; With Their Compositions, Imitations, Adulterations, And Medicinal Uses, Being a General Book of Formulæ and Recipes For Daily Reference in the Laboratory and at the Counter.
Fourth edition, corrected, improved, and very much enlarged.
By James Rennie, M. A., Editor of the Quarterly Journal of Foreign Medicine; the Pharmacopeia Universalis; Author of a Conspectus of Prescriptions in Medicine, Surgery, and Midwifery; the Pharmacopeia Imperialis, &c. &c.
London: Baldwin and Cradock. 1837.
London: Thomas Curson Hansard, Paternoster Row.


LAC. Gum Lac. A preparation used in the arts, and sold in various forms, such as lump lac, seed lac, shell lac, and stick lac. It is formed by the puncture of an insect (Coccus Lacca) on branches of several species of trees, such as Ficus Indica, Rhamnus Jujuba, &c. Seed lac is much used in varnishing, and in making sealing-wax.

Medicinally it is prescribed in form of tincture and of garle as a slight stimulatn. (Jourdan.)
LAC VIRGINIS. Virgin's Milk. Take 3iij of acetate of lead, 3iv of alum dissolved in 3xij of rose water. Mix for cosmetic.

LACCIC ACID. New. This acid was discovered by M. John, in Lac.

LACCIN. New. This principle is intermediate between eax and resin, and is contained in lac. (Funke.)

LACQUERS for metals are a species of varnish used to change the colour and lustre of the article, of which the gold-coloured lacquer for watch cases and keys is an example. Take 3vj of seed lac, 3 ij each of gamboge and amber, gr. xxiv of extract of red sandal-wood in water, gr. 1x of dragon's blood, gr. xxxvj of pure spirit of wine. First grind the amber, lac, gamboge, and dragon's blood on a porphyry slab; then, after making an infusion of the spirit of wine with the sandal-wood, mix thewhole to make a varnish. The metal is heated when it is applied.

LAMP BLACK is the soot of fir and other resinous woods, obtained in manufacturing tar and turpentine;M but may be procured extemporaneously for painting, by holding a plate over the flame of candle, and adding gum. It is a good substitute for Indian ink. (FIELD.)

LARDNER'S PREPARED CHARCOAL. Triturate chalk with charcoal or ivory black.

LITMUS: LACMUS. L. Lacmus Tinctorius. D. Litmus, Turnsol, or Archel, the prepared Thallus of  Roccella tinctoria. Take a quantity of archel, reduce it to powder, add to it  a half the quantity of barilla, or pearlash, and moisten it with urine till it ferments, and becomes of a violet colour; then cut it into small portions and dry it. The watery infusion, or unsized paper dyed with it, is very decolate test for the minutest portion of acid, changing from violet blue to red.

LUTEOLINE. The colouring principle of Reseda luteola, which forms acicular crystals, and is rather acid than alkaline. (CHEVREUL.)