Prop., &c. Small white scales, soluble in 570 parts of water; the solution reddens litmus paper; dissolves in the alkalies, forming alkaline molybdates, from which it is again precipitated by strong acids. It is used in the preparation of molybdenum blue, and in calico-printing, but its scarcity precludes its extensive employment in the arts. Molybdate of ammonium is the salt principally used in dyeing. Silks and cottons passed through a solution of this salt, then through a bath soured with hydrochloric acid, and, lastly (without washing), through another of protochloride of tin, are dyed of a rich and permanent blue colour. A solution of molybdate of ammonia in excess of nitric acid forms a valuable agent as a test for phosphates, with which it gives a beautiful yellow precipitate (phospho-molybdate of ammonia). See Phosphoric acid.
MOLYB′DENUM. Mo. A very rare metal, having a white colour, discovered by Hielm in 1782.
Prep. By exposing molybdic acid, mixed with charcoal and placed in a covered crucible, to the strongest heat of a smith’s forge.
Prop., &c. It is brittle and very infusible; when heated in contact with the air, it is converted into molybdic anhydride, MoO3.
MOMOR′DICINE. See Elaterin.
MOMRAUGHAN FOR HARNESS, &c. A correspondent of the ‘Field’ newspaper gives the following formulæ for momraughan, a substance used in India for preserving saddles and every description of leather. It is made as follows:—1 lb. white wax, 3 lb. mutton fat, 1 pint spirits of turpentine; melt, and mix well together while liquid. The saddle or leather should be rubbed well with a lime in the sun, then scrubbed with a brush with soap and water; when thoroughly dry, rub it well with the momraughan (letting it soak in) in the sun. One tablespoonful will be enough for a saddle. Another recipe is:—1 pint neats-foot oil, 2 oz. beeswax, 2 oz. spirits of turpentine, other directions as above. This latter mixture, with the addition of 1 oz. Burgundy pitch, makes a very good waterproof composition for boots.
MONE′SIA. Syn. Monesia bark, Buranheim b.; Cortex monesiæ, L. The bark of Chrysophyllum Buranheim, a tree growing in the Brazils. The rough, imported extract of this drug also commonly passes under the name of MONESIA. It is astringent, and possesses no advantage over rhatany or catechu.—Dose (of the latter), 18 to 20 gr.
MONE′SIN. A peculiar acrid principle, analogous to saponin, found in monesia bark, to the extent of 4·7%.
MONOBROMATED CAMPHOR. See Camphor, monobromated.
MONOMA′NIA. See Insanity.