sperm whale or cachalot Vka-sho-.lat, 'ka-sho-.loN Thickset, blunt¬ snouted toothed whale ( Physeter catodon, family Physeteridae) with small, paddlelike flippers and rounded humps on the back. Sperm whales have an enormous head, squarish in profile, and a narrow, underslung lower jaw with large conical teeth that fit into sockets in the toothless upper jaw when the mouth is closed. They are dark blue-gray or brown¬ ish. (Herman Melville’s Moby-Dick was presumably an albino.) The male grows to 60 ft (18 m). Herds of 15-20 live in temperate and tropical waters worldwide. They commonly dive to 1,200 ft (350 m), feeding primarily on cephalopods. The whales have been hunted for their spermaceti (a waxy substance in the snout, used in ointments and cosmetics) and for ambergris. The pygmy sperm whale (genus Kogia) is a black dolphinlike whale, about 13 ft (4 m) long, of the Northern Hemisphere that lacks commercial value.
spermatophyte See seed plant
Sperry, Elmer (Ambrose) (b. Oct. 12,1860, Cortland, N.Y., U.S.—d. June 16, 1930, Brooklyn, N.Y.) U.S. inventor and industrialist. He opened his own factory in Chicago at the age of 20 to make dynamos and arc lamps. He designed an electrical industrial locomotive and motor trans¬ mission machinery for streetcars and later made electric automobiles pow¬ ered by his patented battery. He invented processes for salvaging tin and producing white lead and for manufacturing fuse wire. His greatest inven¬ tions sprang from the gyroscope (until then considered only a toy), which, once properly aligned, always points to true north. His gyrocompass was first installed on the battleship Delaware in 1911. He extended the gyro principle to guidance of torpedoes, to gyropilots for the steering of ships and for stabilizing airplanes, and finally to a ship stabilizer. In all, he founded eight manufacturing companies and took out more than 400 patents.
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Spengler, pencil drawing by K. Gross- mann, 1920; in a private collection
DEUTSCHE FOTOTHEK, DRESDEN
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1800 I Sperry ► spider
Sperry, Roger (b. Aug. 20, 1913, Hartford, Conn., U.S.—d. April 17, 1994, Pasadena, Calif.) U.S. neurobiologist. He earned a doctorate in zoology from the University of Chicago. He studied functional special¬ ization in the hemispheres of the cerebral cortex, examining animals and then humans with epilepsy in whose brains the corpus callosum had been severed. His research showed that the left side of the brain is normally dominant for analytical and verbal tasks and the right for spatial tasks, music, and certain other areas. His techniques laid the groundwork for much more specialized explorations. He shared a 1981 Nobel Prize with David Hubel and Torsten Wiesel.
Spey VspaA, River River, northeastern Scotland. It rises in the Cor- rieyairack Forest and flows 107 mi (172 km) northeast across the High¬ lands into the North Sea. It is noted for salmon fishing, and its valley is the site of high-quality whisky distilleries.
sphagnum See peat moss
sphalerite Vsfa-lo-.riA or blende or zincblende Zinc sulfide (ZnS), the chief ore mineral of zinc. It is found associated with galena in most important lead-zinc deposits. The most important deposits are in the Mississippi River valley (U.S.),
Poland, Belgium, and North Africa.
See also sulfide mineral.
sphere In geometry, the set of all points in three-dimensional space lying the same distance (the radius) from a given point (the centre), or the result of rotating a circle about one of its diameters. The components and properties of a sphere are analo¬ gous to those of a circle. A diameter is any line segment connecting two points of a sphere and passing through its centre. The circumference is the length of any great circle, the intersection of the sphere with any plane passing through its centre. A meridian is any great circle passing through a point designated a pole. A geodesic, the shortest distance between any two points on a sphere, is an arc of the great circle through the two points. The formula for determining a sphere’s surface area is 47tr 2 ; its volume is determined by ( 4 /3)kP. The study of spheres is basic to terrestrial geog¬ raphy and is one of the principal areas of Euclidean geometry and elliptic GEOMETRY.
sphere, celestial See celestial sphere
sphere of influence In international politics, a state’s claim to exclu¬ sive or predominant control over a foreign area or territory. Beginning in the late 1880s, European colonial powers undertook legal agreements consisting of promises not to interfere with each other’s actions in mutu¬ ally recognized spheres of influence in Africa and Asia. After colonial expansion ceased, geopolitical rather than legal claims to spheres of influ¬ ence became common, examples being the U.S. claim to dominance in the Western Hemisphere under the much-earlier Monroe Doctrine and the Soviet Union’s expansion of its sphere of influence to eastern Europe fol¬ lowing World War II. See also Iron Curtain.
spherical coordinate system In geometry, a coordinate system in which any point in three-dimensional space is specified by its angle with respect to a polar axis and angle of rotation with respect to a prime merid¬ ian on a sphere of a given radius. In spherical coordinates a point is speci¬ fied by the triplet (r, 0, (p), where r is the point’s distance from the origin (the radius), 0 is the angle of rotation from the initial meridian plane, and cp is the angle from the polar axis (analogous to a ray from the origin through the North Pole).
sphinx Mythological creature with a lion’s body and a human’s head. It figures prominently in Egyptian and Greek art and legend. The winged sphinx of Thebes was said to have terrorized people by demanding the answer to a riddle taught to her by the Muses —What is it that has one voice and yet becomes successively four-footed, then two-footed, then three¬ footed?—and devoured every person who answered incorrectly. When Oedipus correctly answered “man”—who crawls on all fours in infancy, walks on two feet when grown, and leans on a staff in old age—the sphinx killed herself. The earliest and most famous example in art is the Great Sphinx at Giza in Egypt, built c. 2500 bc. The sphinx appeared in the Greek world c. 1600 bc and in Mesopotamia c. 1500 bc. See photograph above.
The Great Sphinx at Giza, 4th dynasty
E. STREICHAN/SHOSTAL ASSOCIATES
sphinx moth See hawk moth
sphynx cat \'sfiqks\ Breed of hairless domestic cat, founded on two spontaneous mutations in shorthaired cats. The first occurred in 1975 when Jezabelle, a stray, produced a hairless female kitten, Epidermis, fol¬ lowed by another the next year. The second occurred in 1978, when a male and two female hairless kittens were rescued from the streets of Tor¬ onto. Sphynx cats must be bathed regularly to keep the skin free of the oils that the coat on a normal cat absorbs, and the very large ears must be cleaned regularly to rid them of dust and dirt and prevent wax buildup.
spice and herb Dried parts of various plants cultivated for their aro¬ matic, savory, medicinal, or otherwise desirable properties. Spices are the fragrant or pungent products of such tropical or subtropical species as cardamom, cinnamon, clove, ginger, and pepper; spice seeds include ANISE, caraway, cumin, fennel, poppy, and sesame. Herbs are the fragrant leaves of such plants as basil, marjoram, mint, rosemary, and thyme. The most notable uses of spices and herbs in very early times were in medicine, in the mak¬ ing of holy oils and unguents, and as aphrodisiacs; they were also used to flavour food and beverages and to inhibit or hide food spoilage. Trade in spices has played a major role in human history. Important early trade routes, including those between Asia and the Middle East and between Europe and Asia, were initially forged to obtain exotic spices and herbs. The 15th-century voyages of discovery were launched largely as a result of the spice trade, and in the 17th century Portugal and the British, Dutch, and French East India companies battled furiously for dominance (see British East India Co.; Dutch East India Co.; French East India Co.).