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litmus

(Encyclopedia)litmus, organic dye usually used in the laboratory as an indicator of acidity or alkalinity (see acids and bases). Naturally pink in color, it turns blue in alkali solutions and red in acids. Commonly...

logwood

(Encyclopedia)logwood, small, thorny tree (Haematoxylon campechianum) of the family Leguminosae (pulse family) native to tropical America and introduced into other tropical regions. The brown-red heartwood is the s...

Lakeland terrier

(Encyclopedia)Lakeland terrier, breed of strong working terrier developed in the 18th and 19th cent. in the Lake District of England. It stands about 14 in. (35.6 cm) high at the shoulder and weighs about 17 lb (7....

Palmer, Alexander Mitchell

(Encyclopedia)Palmer, Alexander Mitchell päˈmər [key], 1872–1936, American politician, b. Moosehead, Pa. Admitted (1893) to the bar, he built up a large law practice, became a leader in the state Democratic pa...

Rocky Mountain spotted fever

(Encyclopedia)Rocky Mountain spotted fever, infectious disease caused by a rickettsia. The bacterium is harbored by wild rodents and other animals and is carried by infected ticks of several species that attach the...

Benedict's solution

(Encyclopedia)Benedict's solution, deep-blue alkaline solution used to test for the presence of the aldehyde functional group, −CHO. The substance to be tested is heated with Benedict's solution; formation of a b...

bloodletting

(Encyclopedia)bloodletting, also called bleeding, practice of drawing blood from the body in the treatment of disease. General bloodletting consists of the abstraction of blood by incision into an artery (arterioto...

beryl

(Encyclopedia)beryl bĕrˈĭl [key], mineral, a silicate of beryllium and aluminum, Be3Al2Si6O18, extremely hard, occurring in hexagonal crystals that may be of enormous size and are usually white, yellow, green, b...

zinnia

(Encyclopedia)zinnia, any species of the genus Zinnia of the family Asteraceae (aster family), native chiefly to Mexico, though some range as far north as Colorado and as far south as Guatemala. The common zinnia o...

Taxco

(Encyclopedia)Taxco täsˈkō [key], town (1990 pop. 43,836), Guerrero state, S Mexico. Founded in 1529 as a silver-mining community, Taxco was also an important stop between Mexico City and Acapulco in Spanish col...