Sunday, October 16, 2005


A vaccine can confer active immunity against a specific harmful agent by stimulating the immune system to attack the agent. Once stimulated by a vaccine, the antibody-producing cells, called B lymphocytes,

Wednesday, July 27, 2005

Davenport, Thomas

A blacksmith in Brandon, Vt., Davenport began experimenting with electromagnets after observing one in use at an ironworks in Crown Point, N.Y., in 1831. By 1834 he had

Monday, July 25, 2005


Born of a well-to-do Athenian family, Xenophon grew up during the great war between Athens and Sparta (431–404 BC) and served in the elite force of Athenian cavalry. He and his well-to-do contemporaries sat at the feet of Socrates, were critical of the extreme form of democracy under which they lived, and sympathized with the right-wing revolutionaries who seized power for short

Saturday, July 23, 2005

Hohenlohe-ingelfingen, Kraft, Prinz Zu

The son of Adolf, Prinz zu Hohenlohe-Ingelfingen, he joined the Prussian Guard Artillery in 1845. During the Seven Weeks' War, Hohenlohe led the Guard Reserve Artillery with great success against the Austrian right wing in the decisive Prussian victory of Königgr

Wednesday, July 06, 2005

Soto, Hernando De

Hernando also spelled  Fernando  Spanish explorer and conquistador who participated in the conquests of Central America and Peru and, in the course of exploring what was to become the southeastern United States, discovered the Mississippi River.

Wednesday, June 29, 2005


A niece of Empress Anna (reigned 1730–40), Anna Leopoldovna married a nephew of the Holy Roman emperor Charles VI in 1739 and gave birth to a son, Ivan (Aug. 2 [Aug. 13], 1740), who was named heir to the Russian throne by Empress Anna in 1740, shortly before she

Wednesday, June 15, 2005

Red River

Also called  Red River Of The South,   navigable river rising in the high plains of eastern New Mexico, U.S., and flowing southeast across Texas and Louisiana to a point northwest of Baton Rouge, where it enters the Atchafalaya River (q.v.), which flows south to Atchafalaya Bay and the Gulf of Mexico. Until the mid-20th century, the Red River contributed flow to both the Atchafalaya and, via the Old River, the Mississippi.