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tained from the root hellebore (Veratrum) and from sabadilla seeds as a white crystalline powder, having an acrid, burning taste. It is sometimes used externally, as in ointments, in the local treatment of neuralgia and rheumatism. Called also veratria, and veratrina.

extracted from the root of a South African plant of the genus Vernonia, as a deliquescent powder, and used as a mild heart tonic.

aterial, such as hay, straw, tow, paper, or old rope yarn, used for retaining a charge of powder in a gun, or for keeping the powder and shot close; also, to diminish or avoid the effects of windage. Also, by extension, a dusk of felt, pasteboard, etc., serving a similar purpose.

A kind of fine sand from the banks of the Trent, used as a polishing powder. [Eng.]

in America; abele. -- White poppy (Bot.), the opium-yielding poppy. See Poppy. -- White powder, a kind of gunpowder formerly believed to exist, and to have the power of exploding without noise. [Obs.] A pistol charged with white powder. Beau. & Fl. -- White precipitate. (Old Chem.) See under Precipitate. -- White ra…

e genus Aleyrodes, allied to scale insects. They are usually covered with a white or gray powder.

Chalk prepared in an impalpable powder by pulverizing and repeated washing, used as a pigment, as an ingredient in putty, for cleaning silver, etc. Whiting pollack. (Zoöl.) Same as Pollack. -- Whiting pout (Zoöl.), the bib, 2.

Covered with an opaque white powder.

A blue dyestuff, or coloring matter, consisting of the powdered and fermented leaves of the Isatis tinctoria. It is now superseded by indigo, but is somewhat used with indigo as a ferment in dyeing. Their bodies . . . painted with woad in sundry figures. Milton. Wild woad (Bot.), the weld (Reseda luteola). See Weld. -…

d. -- Wood fiber. (a) (Bot.) Fibrovascular tissue. (b) Wood comminuted, and reduced to a powdery or dusty mass. -- Wood fretter (Zoöl.), any one of numerous species of beetles whose larvæ bore in the wood, or beneath the bark, of trees. -- Wood frog (Zoöl.), a common North American frog (Rana sylvatica) which lives…

A complex nitrogenous substance related to urea and uric acid, produced as a white powder; -- so called because it forms yellow salts, and because its solution forms a blue fluorescence like quinine.

A glucoside extracted from Persian berries as a yellow crystalline powder, used as a dyestuff.

tain kinds of decayed wood, as the beech, oak, birch, etc., and extracted as an amorphous powder resembling indigo.

s. The name is extended to other ferments of the same genus. See Saccharomyces. -- Yeast powder, a baling powder, -- used instead of yeast in leavening bread.

precipitate (Med. Chem.), an oxide of mercury which is thrown down as an amorphous yellow powder on adding corrosive sublimate to limewater. -- Yellow puccoon. (Bot.) Same as Orangeroot. -- Yellow rail (Zoöl.), a small American rail (Porzana Noveboracensis) in which the lower parts are dull yellow, darkest on the bre…

luminium group, found in gadolinite and other rare minerals, and extracted as a dark gray powder. Symbol Y. Atomic weight, 89. [Written also ittrium.]

pigment obtained, usually by roasting cobalt glance with sand or quartz, as a dark earthy powder. It consists of crude cobalt oxide, or of an impure cobalt arseniate. It is used in porcelain painting, and in enameling pottery, to produce a blue color, and is often confounded with smalt, from which, however, it is disti…

vitriol (Chem.), zinc sulphate. See White vitriol, under Vitriol. -- Zinc white, a white powder consisting of zinc oxide, used as a pigment.

The oxide of zirconium, obtained as a white powder, and possessing both acid and basic properties. On account of its infusibility, and brilliant luminosity when incandescent, it is used as an ingredient of sticks for the Drummomd light.

ediate between the metals and nonmetals, obtained from the mineral zircon as a dark sooty powder, or as a gray metallic crystalline substance. Symbol Zr. Atomic weight, 90.4.