snowy heron: see egret.

heron, common name for members of the family Ardeidae, large wading birds including the bittern and the egret, found in most temperate regions but most numerous in tropical and subtropical areas. Unlike the remotely related cranes and ibises, which fly with their heads extended straight forward, herons fly with their necks folded back on their shoulders. Their plumage is soft and drooping and, especially at breeding time, there may be long, showy plumes on the head, breast, and back. Herons are usually solitary feeders, patiently stalking their prey (small fish and other aquatic animals) in streams and marshes and then stabbing them with their sharp, serrated bills. Most herons roost and nest in large colonies called heronries; others are gregarious only at breeding time; and some are entirely solitary. The nests vary from a sketchy platform of twigs high in a tree to a bulky mass of weeds and rushes built on the ground among the marsh reeds. American herons include the great and little blue herons, the green heron, the yellow-crowned and the black-crowned night herons (the latter known also as night quawk, because of its cry), and the Louisiana heron, called by Audubon "the lady of the waters." The great white heron of Florida, a little larger (50 in./125 cm long) than the great blue, is a striking bird sometimes confused with the American egret. Other large white herons are common in Africa. The European night heron ranges to India and N Africa. The odd looking shoe-billed heron (or stork, a misnomer) is found along the White Nile and the boat-billed heron in tropical America. Herons are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Ciconiiformes, family Ardeidae.

boat-billed heron or boatbill, a tropical New World heron, Chochlearius chochlearius. With shorter legs and a squatter appearance than most herons, this bird is remarkable chiefly for its broad bill, which is shaped like an overturned boat. Its coloring is dull brown, gray, and black and is similar in both the male and female. It is a nocturnal, shallow-water feeder, living on a diet of fishes and insects; it roosts and nests in trees. The boat-billed heron inhabits mangrove swamps from Mexico to S Brazil. It is classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Ciconiiformes, family Ardeidae.

Heron of Alexandria or Hero, mathematician and inventor. The dates of his birth and death are unknown; conjecture places them between the 2d cent. B.C. and the 3d cent. A.D. He is believed to have lived in Alexandria; although he wrote in Greek, his origin is uncertain. Several of his works survive either in Greek or in Latin translation. He wrote on the measurement of geometric figures, and a formula for finding the area of a triangle has been ascribed to him. Known for his study of mechanics and pneumatics, he invented many contrivances operated by water, steam, or compressed air; these include a fountain, a fire engine, siphons, and an engine in which the recoil of steam revolves a ball or a wheel.

Bork, Robert Heron, 1927-, American jurist, b. Pittsburgh. He received his law degree from the Univ. of Chicago in 1953, and served as professor of law at Yale Univ. (1962-73, 1977-81), U.S. Solicitor General (1973-77; see Watergate affair.), and judge for federal Circuit Court of Appeals for the District of Columbia (1982-88). In 1987, President Ronald Reagan nominated Bork to the U.S. Supreme Court. An outspoken conservative, Bork was widely reviled for his apparent opposition to advancement in civil liberties. After lengthy and acrimonious confirmation hearings, he was ultimately voted down by the Senate, 58-42. Bork resigned from the federal court in Feb., 1988, and became a resident scholar at the American Enterprise Institute.

Any of about 60 species of long-legged wading birds in the same family (Ardeidae) as egrets and bitterns. They are found worldwide but are most common in the tropics. They wade in the shallow waters of pools, marshes, and swamps, catching frogs, fishes, and other aquatic animals. They nest on rough stick platforms in bushes or trees near water. Herons commonly stand with their neck bent in an southern shape and fly with their legs trailing and their head held back. They have broad wings and a long, straight, sharp-pointed bill. They are subdivided into typical herons (including the 50-in., or 130-cm, great blue heron of North America), night herons, and tiger herons.

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or Hero of Alexandria

(flourished circa AD 62, Alexandria, Egypt) Greek mathematician and inventor. He is remembered for his formula for the area of a triangle and for inventing the aeolipile, the first steam engine, which, in his design, was a forerunner of the jet engine. Of his many treatises, one contains a method for approximating the square root of a number. His writings on mechanics include discussions of the five simple machines, mechanical problems of daily life, and the construction of many kinds of engines.

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