Search the Dictionary

A colorless crystalline substance, C20H22O10, extracted from certain lichens, as the various species of Rocella. It is a derivative of orsellinic acid. So called because of certain red compounds derived from it. Called also erythric acid.

A colorless crystalline substance, C4H6.(OH)4, of a sweet, cooling taste, extracted from certain lichens, and obtained by the decomposition of erythrin; -- called also erythrol, erythroglucin, erythromannite, pseudorcin, cobalt bloom, and under the name phycite obtained from the alga Protococcus vulgaris. It is a tetra…

A crystalline substance obtained from diseased bile, which becomes blood-red when acted on by nitric acid or ammonia.

A white crystalline alkaloid, extracted from sassy bark (Erythrophleum Guineense).

n in ink from an etched plate. Etching figures (Min.), markings produced on the face of a crystal by the action of an appropriate solvent. They have usually a definite form, and are important as revealing the molecular structure. -- Etching needle, a sharp-pointed steel instrument with which lines are drawn in the gro…

A white, crystalline hydrocarbon, regarded as a polymeric variety of ethylene, obtained in heavy oil of wine, the residue left after making ether; -- formerly called also concrete oil of wine.

An unfermentable sugar, obtained as an uncrystallizable sirup by the decomposition of melitose; also obtained from a Tasmanian eucalyptus, -- whence its name.

ving a fine color. Euchroic acid (Chem.), an organic, imide acid, obtained as a colorless crystalline substance, C12H4N2O8 by heating an ammonium salt of mellitic acid. By reduction it is changed to a dark blue substance (euchrone), -- hence its name.

A mineral occurring in transparent emerald green crystals. It is hydrous arseniate of copper.

A brittle gem occurring in light green, transparent crystals, affording a brilliant clinodiagonal cleavage. It is a silicate of alumina and glucina.

A colorless, crystalline substance extracted from oil of cloves; -- called also clove camphor.

A yellow, crystalline substance, resembling aurin, and obtained by the oxidation of pittacal; -- called also eupittonic acid. [Written also eupitton.]

pertaining to, derived from, or resembling, euxanthin. Euxanthic acid (Chem.), a yellow, crystalline, organic acid, extracted from euxanthin.

A nonnitrogenous, crystalline body, present in small quantity in human fæces.

panse." Savage. Lights . . . high in the expanse of heaven. Milton. The smooth expanse of crystal lakes. Pope.

ory Ligament; k Prosterior Aqueous Chamber between h and i; l Anterior Aqueous Chamber; m Crystalline Lens; n Vitreous Humor; o Retina; p Yellow spot; q Center of blind spot; r Artery of Retina in center of the Optic Nerve.

mist . . . watered the whole face of the ground. Gen. ii. 6. Lake Leman wooes me with its crystal face. Byron.

A stratum in crystalline rock, containing metallic sulphides. Raymond.

A name given to a group of minerals, closely related in crystalline form, and all silicates of alumina with either potash, soda, lime, or, in one case, baryta. They occur in crystals and crystalline masses, vitreous in luster, and breaking rather easily in two directions at right angles to each other, or nearly so. The…

Pertaining to, or derived from, a ferricyanide. Ferricyanic acid (Chem.), a brown crystalline substance, H6(CN)12Fe2, obtained from potassium ferricyanide, and regarded as the type of the ferricyanides; -- called also hydro-ferricyanic acid, hydrogen ferricyanide, etc.