Le Moyne de Bienville, Jean-Baptiste See Jean-Baptiste Le Moyne de Bienville
Le Moyne d'Iberville, Pierre See Pierre Le Moyne d’I berville
Le Nain brothers \b-‘na n \ French painters. By 1630 the three brothers—Antoine (c. 1600-1648), Louis (c. 1600-1648), and Mathieu (c. 1607-1677)—had established a workshop together in Paris. They are said to have worked in harmony, often collaborating on the same picture. Most notable of their works are the dignified and sympathetic genre paint¬ ings of peasant life. Their realism is unique in 17th-century French art. None of the brothers’ works bears more than a surname, and today they are treated as a single painter.
Le Notre \b-'no-tr 3 \, Andre (b. March 12, 1613, Paris, France—d. Sept. 15, 1700, Paris) French landscape architect. In 1637 he succeeded his father as master gardener to Louis XIII at the Tuileries Palace in Paris; he redesigned its gardens and extended the main avenue that later became the Champs-Elysees. Louis XIV placed him in charge of planning the gardens at the Palace of Versailles, which Le Notre transformed from a muddy swamp to a park of splendid vistas. He designed numerous other parks and gardens in France, including those at Saint-Germain-en-Laye, Saint- Cloud, and Fontainebleau, and probably St. James’s Park in London. His designs later influenced Pierre-Charles L'Enfant.
Le Pen, Jean-Marie (b. June 20, 1928, La Trinite, France) French nationalist politician. He was elected in 1956 to the National Assembly as its youngest member. Le Pen helped to found the National Front in 1972, becoming the party’s leader later that year. The party emphasized the threat to France posed by immigration, particularly of Arabs from France’s former North African colonies. The party also opposed Euro¬ pean integration, favoured the reintroduction of capital punishment, and sought prohibitions on the building of additional mosques in France. Le Pen ran several times for the presidency; though he captured less than 1% of the vote in 1974, in 1988 and 1995 he won some 15%. In the presi¬ dential election of 2002 Le Pen finished second in the first round of vot¬ ing, winning 18%, though he was easily defeated in the second round by Jacques Chirac. Le Pen was widely regarded as the leader of French neo- fascism, and his National Front party constituted the main right-wing oppo¬ sition to the country’s mainstream conservative parties from the 1970s through the turn of the 21st century.
Le Van Duyet Vla-'van-dzhu-'yetV (b. 1763, Quang Ngai province, Viet.—d. July 30, 1832, Saigon) Vietnamese military strategist and gov¬ ernment official. From his youth he was attached to the Vietnamese court. He acted as adviser to successive emperors and helped Prince Nguyen Anh (the future emperor Gia Long, founder of the Nguyen dynasty) con¬ quer all of Vietnam, making use of Western armaments and military tech¬ niques. When Gia Long’s successor ordered the persecution of Roman Catholic missionaries, Duyet refused; he was indicted posthumously for his defiance but later was honoured.
leaching Loss of soluble substances and colloids from the top layer of soil by percolating precipitation. The materials are carried downward and
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Leacock ► leaf insect I 1087
are generally redeposited in a lower layer. This transport results in a porous and open top layer and a dense, compact lower layer. In areas of extensive leaching, the remaining quartz and hydroxides of iron, manga¬ nese, and aluminum form laterite. In such areas rapid bacterial action results in the absence of humus in the soil, because fallen plant material is oxidized and the products are leached away.
Leacock, Stephen (Butler) (b. Dec. 30, 1869, Swanmore, Hamp¬ shire, Eng.—d. March 28, 1944, Tor¬ onto, Ont., Can.) British-born Canadian writer and lecturer. He immigrated to Canada with his par¬ ents at age six. Though he taught economics and political science at McGill University (1903-36) and wrote extensively on history and political economy, his true calling was humour. His fame rests on his many books of lighthearted sketches and essays, beginning with Literary Lapses (1910) and Nonsense Novels (1911). His humour is typically based on a comic perception of social foibles and the incongruity between appearance and reality in human conduct.
lead Metallic chemical element, chemical symbol Pb, atomic number 82. Lead is a soft, silvery white or grayish, malleable, ductile, dense metal that conducts electricity poorly. Its stable isotopes are all end products of radioactive decay of uranium and other heavy elements. Known since ancient times, lead is so durable and resistant to corrosion that Roman lead pipes are still usable. Lead is used in roofing, as cable coverings, and in pipes, conduits, and structures. Other uses are in storage batteries, ammunition, and low-melting-point alloys (e.g., solder, pewter) and as shielding against sound, vibrations, and radia¬ tion. Lead is rarely found free in nature; its major ore is the sulfide GALENA (PbS). Because it and its compounds are poisons (see lead poisoning), lead-based paints and gasoline additives have been phased out in many countries. Lead in compounds has valence 2 and 4; an oxide (litharge, PbO) is the most widely used. Lead compounds are added to lead crystal (see glass), glazes, and ceramics and are used as pigments, drying agents for paints and varnishes, insecticides and herbicides, and fireproofing agents and in matches, explosives, and pyrotechnics. Almost half of all lead is recovered from recycled scrap. The “lead” in pencils is graphite.
lead-2 T 0 dating Method of dating that makes use of the ratio of the amount of the radioactive isotope lead-210 to that of the stable isotope lead-206. The method has been applied to the ores of uranium. Lead-210 dating is particularly useful for determining the ages of relatively recent marine sediments and so has been applied to studies concerned with the impact of human activity on the aquatic environment.
lead glance See galena
lead poisoning or plumbism Poisoning by accumulation of lead in the body. Large doses cause gastroenteritis in adults and brain disorders in children. Anemia, constipation and abdominal spasm, confusion, a pro¬ gressive paralysis, and sometimes brain cancer result from chronic expo¬ sure. Children are particularly susceptible to nerve and brain damage; sensitive tests show that even low levels of lead can harm children and are linked to behavioral problems. Sources in the home include lead-based paint, lead drinking-water pipes, and lead-glazed tableware. Babies, who put things in their mouths, are at highest risk. Working where lead is used and exposure to some insecticides are other risk factors. The U.S. phase¬ out of lead in gasoline was completed in 1996; similar bans are being implemented worldwide. Treatment involves giving antidotes that bind (see chelate) the lead in the tissues.
Leadbelly orig. Huddie William Ledbetter (b. c. Jan. 21, 1885?, Mooringsport, La., U.S.—d. Dec. 6, 1949, New York, N.Y.) U.S. folk blues singer and songwriter. As a child he learned to play many instru¬ ments; he later worked as an itinerant musician with Blind Lemon Jef¬ ferson. In 1918 he was imprisoned for murder; he was pardoned in 1925 by the governor of Texas, who had visited the prison and heard him sing. Resuming a life of drifting, he was imprisoned for attempted murder in
1930; he was discovered in 1933 by folklorist John Lomax, who secured his release. Under Lomax’s guidance he embarked on a concert tour, pub¬ lished 48 songs with commentary about Depression-era conditions of African Americans (1936), and recorded extensively. He worked with Woody Guthrie in the group the Headline Singers. Leadbelly died penni¬ less, but several of his songs, including “Goodnight, Irene,” “The Mid¬ night Special,” and “Rock Island Line,” soon became standards.