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The great accumulations of snow by sliding downward in ravines until they join together in the river valleys and form glaciers (q.v.), constitute an important factor in the study of phys ical geography. A heavy snowfall is not merely a question of low temperature, but of inflowing and uprising cool moist air. In this respect the physical processes that determine the formation of snow are entirely similar to those that determine the formation of rain. The ordinary limits of snowfall and glaciation at sea level are north of the parallel of 30° north and south of the parallel of 30° south. Snow is an exceedingly poor conductor of heat, owing to the non-homogeneous texture of the mass, which may be considered as composed of alternate thin layers of ice and air. A covering of snow on the ground, or a hut hastily built of blocks of snow, is a perfect protection against the cold storms from the north. The roots of the most tender vegetation prosper under a covering of snow, which, ordinarily, maintains them at a uniform temperature of

about 32° F.

During the winter season snow falls at irregular intervals; sometimes in connection with rain, and a few days of dry air, clear sunshine, and strong wind cause the snow to evaporate and disappear. From an agricultural and a geological point of view the amount of snow lying on the ground at any time is highly important. The United States Weather Bureau publishes monthly maps showing this feature of climatology; a gen eral map has also been compiled showing the normal amount of snowfall for the whole year as a help to the study of the conditions that favor the accumulation of snow and the possible occurrence of a glacial period in North America.

BIBLIOGRAPHY. The principal collection of snow photographs are those that we owe to Dr. Neuhauss, of Berlin, 1892-93; G. Norden skiold, of Stockholm; A. A. Sigson, of Rybinsk, Russia; and, most important of all, those of W. A. Bentley, of Jericho, Vermont. See articles in Appleton's Popular Science Monthly, May, 1898, and in the Monthly Weather Review for May, 1901.

SNOW, LORENZO (1814-1901). An American official, president of the Mormon Church, born at Mantua, Portage County, Ohio. He studied at Oberlin College, in 1836 was converted to Mormonism, and in 1840-43 was a missionary to Great Britain. In 1852 he was elected to the Utah House of Representatives, and until 1882 continued as a member of either the House or the Council. He established Brigham City in Utah in 1855, and organized there a system of coöperative industry. He was sent on missions to Italy in 1849, and to the Sandwich Islands in 1864. In 1889 he was elected president of the Twelve Apostles, and in 1898 president of the Mormon Church. His publications include a translation of the Book of Mormon into Italian, The Only Way to Be Saved (1851), and The Voice of Joseph (1852).

SNOWBALL TREE. Another name for the Guelder rose (q.v.).

SNOWBERRY (Symphoricarpos racemosus). A bushy deciduous shrub of the natural order Caprifoliaceæ, a native of northern North America, and common in shrubberies. It has simple

leaves, small flowers, white inedible berries, about the size of black currants, remaining on the bush after the leaves. The creeping snowberry (Chiogenes serpyllifolia) is a native of North American bogs.

SNOW-BIRD. Any species of bird, usually a finch, associated with snow. In the United States the name is most commonly applied to the juncos (q.v.), but also to the snow-bunting (q.v.). See Plate of SPARROWS.

SNOW-BUNTING, or SNOW-FLAKE. A large finch (Plectrophenax nivalis) of a genus distinguished by the long lark-like straight claw of the hind toe and a similarity to the larks in habits; there is a similar ease and celerity in running along the ground, and the song is very different from that of any of the true buntings. The color of the plumage is very different from most fringilline birds, for white predominates. In summer plumage the back and parts of the wings and tail are black. In winter plumage all the upper parts are rusty brown. The length of an adult is seven inches. The snow-bunting abounds in summer in all parts of the arctic regions, and in winter migrates into the north temperate regions, but is rarely seen even in the Northern United States, except in severe winters, and when snow is plentiful. It feeds largely on the seeds of grasses and weeds, and is often seen in company with longspurs (q.v.). See Plate of BUNTINGS AND GROSBEAKS.

SNOW-COCK. A name given by Anglo-Indian sportsmen to two different birds found near the snow-line in the Himalayas. One is the Tibetan snow-pheasant, a large and active species frequenting the stony heights of all Central Asia. It is Tetraogallus Himalayensis. Other species are found in various other Asiatic mountain ranges. Another snow-cock is the 'jer-monal' (Lerwa nivicola) of the higher Himalayas and Western China.

SNOWDEN, snō'd'n, JAMES Ross (1810-78). an American numismatist, born at Chester. Pa. After graduating at Dickinson College, he settled in Franklin. Subsequently he was State Treasurer (1845-47), treasurer of the United States mint (1847-50), and its director (1853-61). His publications include many pamphlets on coins and his Description of Coins in the United States Mint (1860); Coins of the Bible (1864); and an article on the coins of the United States in the National Almanac (1873).

SNOWDON, snodon. A mountain group in Caernarvonshire, North Wales (Map: Wales, B 3). It is broken by valleys into four minor groups, whose chief peak. Moel-y-Wyddfa ('the conspicuous peak'), is the highest mountain in South Britain, being 3560 feet above sealevel.

SNOW-DROP (so called from the color of the flower), Galanthus. A genus of plants of the natural order Amaryllidaceæ. The bulbous root produces two leaves and one single-flowered leafless stem. The common snow-drop (Galanthus nivalis) is found chiefly in the woods and pastures of Southern Europe. Various species are popular spring flowers in flower gardens.

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SNOW-DROP TREE, or SILVER-BELL TREE (Halesia tetraptera and Halesia diptera). Two shrubs or small trees of the natural order Styracaceæ, with large and veiny pointed deciduous leaves, and showy white flowers, drooping slender pedicels in short

SNOW-DROP TREE (Halesia tetraptera).

SNOWFLAKE (so called from the color of the flower), Leucojum. A genus of nine species of bulbous herbs of the natural order Amaryllidaceæ, natives of the Mediterranean region. The spring snowflake (Leucojum vernum), the

on

racemes or clusters from axillary buds of the preceding year. They are beautiful shrubs for cultivation.

SUMMER SNOWFLAKE.

best known species, produces umbels of sweetscented flowers in March or April. The summer snowflake (Leucojum æstivum) is a beautiful rapidly growing and freely spreading plant. Leucojum autumnale, a Portuguese species, produces drooping flowers in autumn. These plants make the best growth on rich sandy or loamy soils. Propagation is by offsets, obtained as soon as the leaves have become dry.

SNOWFLOWER. See FRINGE-TREE.

SNOW-GOOSE. An Arctic goose (Chen hyperborea) seen in the United States during its migrations, sometimes in vast numbers. It is pure white, except the black wing-quills, washed on the head with reddish; the beak, which is strongly 'toothed,' is pink and the feet reddish. An adult male measures 27 inches long, and weighs 54 pounds. Ross's snow-goose (Chen Rossi) is a miniature of the other, and is known all over the Hudson Bay country as 'horned wavey.' Consult Coues, Birds of the Northwest (Washington, 1874).

SNOW-LEOPARD. The ounce (q.v.).

SNOW LINE. The level on a mountain slope above which snow exists all the year round, or at least very nearly so. The height of this line above sea-level varies greatly both from year to year, and in different localities; it moves up and down within a broad zone, and is determined principally by the temperature, moisture,

and average velocity of the prevailing winds. The average height of the snow line varies from 18,400 feet in the tropical Andes, and 19,000 feet in the Himalayas, down to 6000 feet in Patagonia, and 2000 feet in Greenland. See SNOW; MOUNTAIN; and the articles on the separate mountain ranges, as ALPS, HIMALAYA, etc. SNOW-ON-THE-MOUNTAIN. A euphorbiaceous plant. See SPURGE.

SNOW-PLOW. A machine for clearing roads and railways of snow. The rotary steam snow shovel has been adopted by all the transcontinental lines of the United States and Canada. It consists of a wheel 9 feet in diameter set in a round casing with a flaring front 10 feet square which feeds the snow into the wheel. The wheel contains an inner and outer series of knives pivoted on radial pins, with their surfaces inclined to one another; when they encounter any snow, they are canted, or set so as to slice it off and feed it into the machine. Behind the knives is a fan wheel composed of a number of radial blades. When the wheel revolves the centrifugal force throws the snow to the outside of the wheel, where it meets the inclosing case, and is forced through an opening just behind the headlight. A hood to this opening regulates the direction in which the snow is thrown. The weight of the machine is about twenty tons.

SNOW-SHOEING. The original snow-shoe of America was a frame of light wood, made in the shape of a more or less elongated circle, across which were criss-crossed ligatures of leather, with a bow on the top, into which the foot could be slipped. Snow-shoes are of four permanent main varieties. One is long and narrow and sharp at each end, swelling only slightly in the middle, and slightly turned up at the toe. Another has a turned-up entry which meets the snow nearly squarely, and a trailing pointed after end. These are favorite patterns of all the far north; they are about five feet long and a foot wide in the centre, made of white birch and laced with fine caribou skin webbing, except immediately under the foot, where there is an open bed-cording of thick rawhide. A third kind is broader and shorter, with an oval entry at the fore end and a trailing, though shorter, after end. The fourth set are almost circular, with a stumpy beaver-like trail end. The last two styles are the true 'Montagnais' or mountaineers' shoes. In walking, the shoe is slightly raised and carried partly over and ahead of its fellow, and when the step is completed the swell of the centre of the frame of the rear shoe lies close to the inward curve of the hinder part of the leading shoe. The principal snow-shoe clubs of Canada are those of Montreal

and Quebec. The time record for snow-shoeing is faster than the ordinary cross-country runs. The hundred-yard dash is covered in a little over twelve seconds, and the mile in five minutes forty seconds.

SNOWY OWL. A large owl (Nyctea пусtea) which inhabits the circumpolar region, and appears irregularly in winter in more temperate regions southward. occasionally visiting even the central parts of the United States. It has no 'horns,' is white suffused with reddish brown in summer, but in winter is pure white. Its habits are similar to those of other large owls (q.v.); and in arctic America it feeds mainly upon ptarmigan. Many curious superstitions cling about it in the folk-lore of the northern peoples.

SNUFF. See TOBACCO.

SNUFF-TAKERS. See CONSCIENCE WHIGS. SNY'DERS, FRANS (1579-1657). A Flemish painter, born at Antwerp. He studied under Pieter Brueghel the younger and Hendrick van Balen. His talents won for him the admiration of Rubens, who frequently engaged him to paint fruit, game, and other accessories in his pictures; and in turn Rubens often contributed the figures to the canvases of Snyders. The chief works which they painted together are "Diana's Hunt" (Berlin Museum) and the "Prometheus and the Eagle" (Oldenburg Museum). As a painter of hunting episodes, scenes of violent action. and combats of animals, Snyders stands as very nearly the equal of Rubens. His pictures are seen in all the famous galleries of Europe, that of Madrid possessing no less than twenty-one. There are five of his pictures at the Stockholm Museum; fourteen at the Hermitage, Saint Petersburg; ten at Dresden; and seven at Munich. Among those at Munich is his master piece, "Two Lions Pursuing a Roebuck." A subject quite similar was bequeathed to the Metropolitan Museum, New York City, in 1871.

SOANE, son, Sir JOHN (1753-1837). An English architect, born at White Church, near Reading. In 1788 he was appointed architect to the Bank of England, which remains the best example of his work. He was elected to the Royal Academy in 1802, and became professor of architecture there in 1806. While lecturing he began the foundation of the Soane Museum, which he left to the British nation. It contains a valuable collection of pictures, casts, and antiquities. His written works include Designs for

Public Improvements in London and Westminster

(1827), and Designs for Public and Private

Buildings (1828).

SOAP (AS. sāpe, OHG. seifa, seipfa, Ger. Seife, soap; probably connected with AS. sipan, MHG. sifen, to drip, trickle, Lat. sebum, tallow). A term generally employed in chemistry to describe the metallic salts of the higher fatty acids. In commerce it has a more limited application, being confined to the potassium and sodium salts which are extensively used as detergents. These soaps are also used in a limited way as bases for various dyestuffs, and sometimes for medical purposes. The sodium compounds of fatty acids, being generally efflorescent, harden on exposure to air, and hence are known as hard soaps. The potassium compounds, on the contrary, absorb water under the same conditions and consequently tend to liquefy; hence they are called soft

soaps.

The fats generally used in soap-making include various tallows and greases of animal origin, lard oil, palm oil, olive oil, cotton-seed oil, corn oil, cocoanut oil, stearin, red oil (crude oleic acid), etc. The alkali lves are prepared either by dissolving caustic soda or potash in water to the desired strength, or, as is more often the case in large establishments, at least with the caustic soda lyes, they are made by dissolving carbonate of soda in hot water and then adding the requisite quantity of quicklime for causticizing, boiling and allowing the mass to cool, when the clear lye is drawn from the top.

The solution thus obtained is often strengthened by evaporation or by addition of a further quantity of solid caustic alkali.

The soaps manufactured at present may be classified as follows: (1) Rosin or laundry, settled soaps; (2) toilet soaps, including settled, half-boiled, transparent, and floating varieties; (3) marine soaps; (4) medicated soaps; and (5) manufacturing soaps.

The materials required in manufacturing settled soaps include tallow (alone or mixed with grease and oil), caustic soda solution (18°-22° Baumé), and pickle (saturated salt solution). The operation is carried out in large sheet-iron kettles, circular or square in section, and heated by two steam coils İying on the bottom of the kettle. One coil is perforated with small holes and delivers free steam in fine jets (the 'open coil'); the other serves to heat the contents of the kettle but allows no escape of steam (the 'closed coil'). The various operations are known as stock change, rosin change, strength change, and finish stock change. The 'stock' (i.e. the fatty material) is pumped in liquid state into the kettle and partly spent lye from a previous operation is added, the open coil being used as a heater. A portion of the stock being always somewhat rancid, it unites at once with the lye to form soap, the soap in turn, with the aid of the live steam, emulsifying the rest of the

fat. The open coil is now shut and the closed coil used. From time to time addition of strong fresh lye is made until the contents of the kettle are homogeneous, have a characteristic gummy appearance, and run in long strings from a wooden paddle which has been dipped in the hot liquid. Pickle is now added until the soap becomes insoluble ('grained') and floats on the surface. The contents of the kettle, being al

lowed to cool, separate into two layers, the granular imperfect soap floating on the brine.

The latter, which contains glycerin, is drawn off from the bottom of the kettle and worked for glycerin and salt.

To the soap remaining in the kettle is added fresh strong lye and rosin to the amount of 50 to 100 per cent. of the stock originally used. This mixture is heated by the closed coil until the rosin is saponified and then the kettle is salted out as before. On standing, a lye separates which contains a little glycerin not extracted in the previous process; this lye, too, is worked for its glycerin and salt. The next operation (the 'strength change') is introduced in order to insure complete saponification. For this purpose fresh strong lye (at least 22° Baumé) is added and the mass is kept gently boiling for several hours in the grained condition, strong lye having the same effect on soap as pickle; viz. it renders the soap insoluble. At the conclusion of this operation the kettle contents are allowed to cool and settle, and the drawn off lye, which is not exhausted as in the previous operations, is used to start a new saponification in the stock change. The grained soap is finally reheated and enough cold water added to cause it to pass into solution ('close'). At this stage the heat is turned off, and the kettle contents slowly cool down and stratify in three layers: the soap on top, next an impure dark soap called 'nigre,' and finally a small quantity of strong dark lye too impure for further use. The process of making settled soap without rosin is the same, except that the

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