sand worm, name applied to a number of marine sand-dwelling Worms used as bait in fishing. See Class Polychaeta under Annelida.

sand fly: see midge.

sand dollar, common name for a marine animal in the same phylum as the starfish (see sea star). The sand dollar has a rigid, flattened, disk-shaped test, or shell, made of firmly united plates lying just beneath the thin skin. Small spines that densely cover the test enable the animal to burrow in sand just below the surface. Like other members of its class, the sand dollar is radially symmetrical. It also shows evidence of a secondary bilateral symmetry, i.e., the mouth is centered on the oral (under) surface, but the anus lies near the rear edge of the test. Tube feet are similar to those in other echinoderms and are used for locomotion and to convey small food particles, mostly organic matter found in sand, to the mouth. Tube feet on the upper surface are used for respiration. Sand dollars differ from the closely related heart urchins by their shorter spines and more flattened shape. More convex, short-spined sand dollars are called sea biscuits. Sand dollars are abundant on the sandy bottom of deeper waters on both the Atlantic and Pacific coasts. They are classified in the phylum Echinodermata, class Echinoidea, order Clypeastroida.

sand, rock material occurring in the form of loose, rounded or angular grains, varying in size from .06 mm to 2 mm in diameter, the particles being smaller than those of gravel and larger than those of silt or clay. Sand is formed as a result of the weathering and decomposition of igneous, sedimentary, or metamorphic rocks. Its most abundant mineral constituent is silica, usually in the form of quartz, and many deposits are composed almost exclusively of quartz grains. Many other minerals, however, are often present in small quantities, e.g., the amphiboles, the pyroxenes, olivine, glauconite, clay, the feldspars, the micas, iron compounds, zircon, garnet, tourmaline, titanite, corundum, and topaz. Some sands—e.g., coral sands, shell sands, and foraminiferal sands—are organic in origin. Sand grains may be rounded or more or less angular, and differences in shape and size account chiefly for differences in such important properties as porosity (proportion of interstices to the total mass), permeability to gases and liquids, and viscosity, or resistance to flow. Permeability and viscosity are also affected by the proportion of clayey matter present. The chief agents in accumulating sands into deposits are winds, rivers, waves, and glaciers; sand deposits are classified according to origin as fluviatile, lacustrine, glacial, marine, and eolian. The most extensive superficial deposits are seen in the desert and on beaches. The surface of a sand deposit may be level or very gently sloping, or the sand may be gathered by wind action into ridges called dunes. Sandstone and quartzite rocks are indurated masses of sand, and sand deposits are sometimes formed by the weathering of sandstone and quartzite formations. Sand is used extensively in the manufacture of bricks, mortar, cement, concrete, plasters, paving materials, and refractory materials. It is also used in the metallurgical industry, in the filtration of water, in pottery making, in glassmaking, in the manufacture of explosives, and as an abrasive. Other industrial uses are numerous. Although soils entirely composed of sand are too dry and too lacking in nourishment for the growth of plants, a soil that is to some extent sandy (a "light" soil) is favorable to certain types of agriculture and horticulture, as it permits the free movement of air in the soil, offers less resistance than a clay soil to growing roots, improves drainage, and increases ease of cultivation. Sand to which nutrient solutions have been added is often used in soilless gardening.

Sand, George, pseud. of Amandine Aurore Lucie Dupin, baronne Dudevant, 1804-76, French novelist. Other variant forms of her maiden name include Amantine Lucile Aurore Dupin. Born of an aristocratic father and a lower-class mother, she was reared by her austere paternal grandmother on a country estate in Berry. After entering a convent in Paris, she returned to the countryside and led an unconventional life, donning the male clothes that became a mark of her rebellion. In 1831, after eight years of a marriage of convenience with Baron Dudevant, a country squire, she went with her two children to Paris, obtaining a divorce in 1836. She wrote some 80 novels, which were widely popular in their day, supporting herself and her children chiefly by her writing. Her earlier novels were romantic; later ones often expressed her serious concern with social reform. Her liaisons—with Jules Sandeau, Musset, Chopin, and others—were open and notorious, but were only part of her life. She demanded for women the freedom in living that was a matter of course to the men of her day.

Her first novel, Rose et Blanche (1831), was in collaboration with Jules Sandeau (a shortening of his last name provided her with the pseudonym which she kept all her life), with whom she had previously written articles for the journal Figaro. Of her own novels, La Mare au diable (1846, tr. The Haunted Pool, 1890) and Les Maǐtres sonneurs [the master bell-ringers] (1853) are considered masterpieces. Notable also are Indiana (1832, tr. 1881), Mauprat (1837), Consuelo (1843, tr. 1846), François le champi (1848, tr. Francis the Waif, 1889), La Petite Fadette (1849, tr. Fanchon the Cricket, 1864), and Contes d'une grand'mère (1873, tr. Tales of a Grandmother, 1930), a collection of Breton fairy tales. All these books are distinguished by a romantic love of nature as well as an extravagant moral idealism. She also wrote a number of plays. Much of her work was autobiographical, notably Histoire de ma vie (1854); Elle et lui [she and he] (1859), which concerns her life with Musset; and Un Hiver à Majorque [a winter in Majorca] (1842), about her life with Chopin.

Sand Springs, city (1990 pop. 15,346), Tulsa co., NE Okla., an industrial suburb of Tulsa, on the Arkansas River; founded 1907. There are oil and natural-gas wells and food-processing and chemical industries.

Sand Creek, Colorado, site of a massacre (1864) of Cheyenne by Col. John M. Chivington and his Colorado Volunteers. The Cheyennes, led by their chief, Black Kettle, had offered to make peace and, at the suggestion of military personnel, had encamped at Sand Creek near Fort Lyon while awaiting word from the territory's governor. There they were attacked in a surprise dawn raid on Nov. 29, 1864. Chivington and his men, choosing to ignore a white flag, slaughtered and mutilated hundreds of men, women, and children. The atrocity has been the subject of much controversy, and an effort to unearth the site began in 1998.

Härnösand, city (1990 est. pop. 19,200), capital of Västernorrland co., E Sweden, on the Gulf of Bothnia at the mouth of the Ångermanälven River. Its harbor, icebound in winter, is a center of the coastal trade of N and E Sweden. Forest products are the chief exports of Härnösand. Manufactures include machinery, processed tobacco, and ships. The city was chartered in 1585 and has long been a cultural center of Norrland. It was burned in 1721 by Russians.

Great Sand Dunes National Park and Preserve: see National Parks and Monuments (table).

or bituminous sand

Deposit of loose sand or partially consolidated sandstone that is saturated with highly viscous bitumen. Oil recovered from tar sands, commonly referred to as synthetic crude, is a potentially significant form of fossil fuel. The largest known deposits of tar sands occur in Canada's Athabasca River valley, where commercial projects for synthetic oil production from tar sands are being carried out.

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Any of about six species of shallow-water, bottom-dwelling sharks in the genus Odontaspis (family Odontaspididae), found along tropical and temperate coastlines of all oceans. They are 10–20 ft (3–6 m) long and are brown or gray above, paler below. Voracious but generally sluggish, they have long, slim, pointed teeth and prey on fishes and invertebrates. Two species, the sand tiger (O. taurus) of the Atlantic and the gray nurse (O. arenarius) of Australia, are potentially dangerous.

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Type of art practiced among the Navajo and Pueblo Indians and among Tibetan Buddhists. Sandpaintings are stylized, symbolic pictures (in Tibet, mandalas) prepared by trickling small quantities of crushed, coloured sandstone, charcoal, or pollen on a background of clean smoothed sand. The pictures may include representations of deities, cosmic worlds, animals, lightning, rainbows, plants, and other symbols described in chants that accompany various religious and healing rites.

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or beach flea

Hopping terrestrial crustacean (family Talitridae). The European sand flea (Talitrus saltator) is about 0.6 in. (1.5 cm) long. The long-horned sand flea (T. longicornis), found on the North American Atlantic coast, has antennae the same length as the waxy white body, up to 1 in. (2.5 cm) long. During the day, sand fleas lie buried near the high-tide mark; at night, they forage for organic debris. The common sand flea (Orchestia agilis, or platensis) lives along Atlantic coasts of Europe and the Americas.

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Any of several species in the dipteran family Phlebotomidae (sometimes considered part of the family Psychodidae) with aquatic larvae that live in the intertidal zone of coastal beaches, in mud, or in wet organic debris. The genus Phlebotomus transmits the pappataci fever virus, and in parts of South America, Africa, and Asia it carries the protozoan parasites that cause kala azar, Oriental sore, espundia, and bartonellosis. The name is also used for species of the blackfly and biting midge families.

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Hill, mound, or ridge of windblown sand or other loose material such as clay particles. Dunes are commonly associated with desert regions and seacoasts, and there are large areas of dunes in nonglacial parts of Antarctica.

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Any echinoderm (order Clypeastroida, class Echinoidea) that has a coinlike, thin-edged body. Five “petals” spread out from the center of the upper body. It burrows in sand, feeding on organic particles wafted to the mouth, located in the center of the body's underside. Small spines covering the body are used for digging and crawling. Tests (external skeletons) of the common sand dollar (Echinarachnius parma), which often wash up on beaches in North America and Japan, are 2–4 in. (5–10 cm) in diameter.

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Mineral, rock, or soil particles that are 0.0008–0.08 in. (0.02–2 mm) in diameter. Most rock-forming minerals are found in sand, but quartz is by far the most common. Most sands also contain a small quantity of feldspar, as well as white mica. All sands contain small quantities of heavy rock-forming minerals, including garnet, tourmaline, zircon, rutile, topaz, pyroxenes, and amphiboles. In the pottery and glassmaking industries very pure quartz sands are used as a source of silica. Similar sands are used for lining the hearths of steel furnaces. Molds used in foundries for casting metal are made of sand with a clay binder. Quartz and garnet sands are used extensively as abrasives. Among ordinary sand's many uses, it is a basic ingredient of mortar, cement, and concrete. Seealso tar sand.

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Accumulation of fragments of durable, usually dark, heavy minerals (those with a density greater than that of quartz). These accumulations are found in streambeds or on beaches where stream flow and wave energy are sufficient to carry away low-density material but not the heavy minerals. Thus, heavy minerals resistant to weathering and abrasion concentrate in these areas, though they may be only minor constituents of inland rocks. Placer mining of such deposits yields magnetite, cassiterite, and zircon, as well as gold, platinum, and other rare metals.

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orig. Amandine-Aurore-Lucile Dupin

(born July 1, 1804, Paris, France—died June 8, 1876, Nohant) French writer. During childhood she gained a love of the countryside that would inform most of her works. Married in 1822, she soon tired of her husband, Casimir Dudevant, and began a series of liaisons; her lovers included Prosper Mérimée, Alfred de Musset, and, most importantly, Frédéric Chopin. She became famous (under her pseudonym) with her novel Indiana (1832), a protest against conventions that bind an unhappy wife to her husband. Lélia (1833) extended her iconoclastic views on social and class associations. Similar themes, along with her sympathy for the poor, are evident in her finest works, the so-called rustic novels, including The Devil's Pool (1846), The Country Waif (1848), and Little Fadette (1849).

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Natural area, south-central Colorado, U.S. It lies at the eastern edge of the San Luis Valley along the western base of the Sangre de Cristo Mountains. Established in 1932 as a national monument, the 150,000-acre (60,700-hectare) region contains some of the highest inland sand dunes in the U.S., with changing crests that rise to 700 ft (215 m). In 2000 the Great Sand Dunes National Preserve was created, and after much land acquisition the monument officially became a national park in 2004.

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orig. Amandine-Aurore-Lucile Dupin

(born July 1, 1804, Paris, France—died June 8, 1876, Nohant) French writer. During childhood she gained a love of the countryside that would inform most of her works. Married in 1822, she soon tired of her husband, Casimir Dudevant, and began a series of liaisons; her lovers included Prosper Mérimée, Alfred de Musset, and, most importantly, Frédéric Chopin. She became famous (under her pseudonym) with her novel Indiana (1832), a protest against conventions that bind an unhappy wife to her husband. Lélia (1833) extended her iconoclastic views on social and class associations. Similar themes, along with her sympathy for the poor, are evident in her finest works, the so-called rustic novels, including The Devil's Pool (1846), The Country Waif (1848), and Little Fadette (1849).

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