atic acid, which gives rise to a yellow, oilylooking liquid, which collects at the bottom of the vessel. This liquid is the bisulphuret of hydrogen. It cannot be kept, for it undergoes spontaneous decomposition even in well-closed vessels, being converted into sulphur and sul phureted hydrogen. Sulphur has the property of combining with carbon, and of forming a very remarkable compound, called bisulphuret of carbon. It is formed as follows:-Fill a porcelain tube with charcoal, and make it pass through a furnace in such a way, that one end shall be considerably elevated above the other. To the lower extremity lute a wide glass tube, of such a length and shape, that its end can be plunged to the bottom of a glass bottle filled with water. To the elevated extremity lute another wide glass tube, filled with small bits of sulphur, and secured at the further end, so that the sulphur may be pushed forward by means of a wire, without allowing the inside of the tube to communicate with the external air. Heat the porcelain tube, and, consequently, the charcoal which it contains, to redness, and continue the heat, till air bubbles cease to come from the charcoal; then push the sulphur slowly, and piece after piece, into the porcelain tube. A substance passes through the glass tube, and condenses, under the water of the bottle, into a liquid. This liquid was obtained by Lampadius in 1796, and described under the name of alcohol of sulphur. It is as transparent and colorless as water; its taste is acid, pungent, and somewhat aromatic; its smell is nauseous and fetid, though quite peculiar; specific gravity 1.27. It boils at 105°, and does not congeal when cooled down to 60°. It is one of the most volatile liquids known, and produces a greater degree of cold by its evaporation than any other substance. It takes fire in the open air, at a temperature scarcely above 620°. It is scarcely soluble in water; but alcohol and ether dissolve it readily. It is composed of sulphur 84.83 and carbon 15.17. Bisulphuret of carbon was found by doctor Brewster to exceed all fluid bodies in refractive power. In dispersive power, it exceeds every fluid substance except oil of cassia, holding an intermediate place between phosphorus and balsam of Tolu. Sulphur combines with boron, silicon and phosphorus, and forms sulphurets of these substances. (For an account of the sulphurets of the metals, see the different metals.)

SULPHURIC ACID. (See Sulphur.)

SULTAN, in Arabic, signifies mighty. The Turkish emperor is called sultan, or grand sultan, although the title of padishah (q. v.) is more dignified. The princes of the family of the khan of the Crim Tartars are also styled sultan. The pacha of Egypt is likewise honored with this title, by the inhabitants of the country, but not at the court of Constantinople. In common life, every person is addressed, out of civility, as sultanum (my lord). The Europeans also call the wives of the sultan, sultanas; but the Turks call them merely first, second, or third wife, &c. The first is she who first bears a son to the sultan. She is likewise called by Europeans the favorite sultana. She has the precedency of all the women of the seraglio, unless her son dies before the sultan, and another of the wives has a son older than any of hers surviving. The title of sullana is applied properly only to one of the wives, who is actually declared wife and empress; but this is rarely done, on account of the expense of a second court, which would be necessary. At Constantinople, only the daughters of the sultan are called sultanas; and they retain this title even after marriage with the officers of the sultan. The daughters of such a marriage are termed kanum sultanas (ladies of the blood). If the mother of the sultan is living, she is styled Walidet-sultana, or sultana Valide. She is treated with great respect, and her son cannot choose a new wife or concubine without her consent. (See Harem.) Sultana is also the name of a Turkish ship of war, carrying about sixty-six guns, with 800 men.

SUMACH (rhus); a genus of plants, belonging to the natural family terebinthacea, consisting of shrubs or small trees, with small, inconspicuous flowers, disposed in racemes or panicles, and leaves usually pinnate, somewhat resembling those of the walnut, but in some species ternate or simple. More than seventy species are known: all have a lactescent juice, more or less acrid, and containing a gumresin.-R. coriaria is found in the countries about the Mediterranean. The young branches, dried and powdered, were used by the ancients for tanning leather; and at the present time, in some parts of Spain and Italy, the black morocco is chiefly prepared with this plant. The roots contain a brown, and the bark a yellow dye. The seeds are in common use at Aleppo, at meals, to provoke an appetite. Both leaves and seeds are used in medicine, as astringent and styptic.-R. typhina is a

shrub, twelve or fifteen feet high, common in the northern parts of the U. States. The young branches are thick, and covered with a dense coating of hairs; hence the common name of stag's horn sumach. The leaves are pinnate, and composed of eleven to fifteen serrated leaflets. The flowers are small and numerous, disposed in an upright hairy panicle, and are succeeded by small berries, which finally turn red, and render this shrub a conspicuous object in the woods. It has been long cultivated in the European gardens for ornament. The berries possess the same properties as those of the preceding, and a very abundant milky juice flows from the bark. This last is pulverized, and employed for tanning.-R. glabra precisely resembles the preceding in habit, and is only distinguished by the smoothness of the leaves and young shoots. It extends farther south, and is common in the Middle States; often overrunning land left for a few years in pasture. The berries dye red, and the branches boiled with the berries afford a black, ink-like tincture. It is likewise cultivated for ornament, in the European gardens, and possesses the same properties as the preceding.-R. pumila is a low, pubescent species, from the mountains of Carolina, which is said to be the most poisonous of the genus.-R. venenata, commonly called dog-wood or poison sumach, is not uncommon in the Northern and Middle States. It attains the height of twelve to twenty feet. The leaves are smooth and entire; the flowers greenish-white, disposed in loose panicles, and succeeded by whitish berries. The poisonous qualities of this plant are well known. Some persons are affected by touching or smelling any part of it, or even by coming within a certain distance; while others appear to be entirely exempt from its influence. When the poison has been communicated, inflammation appears on the skin, in large blotches, in a day or two; soon after, small pustules rise in the inflamed parts, and fill with watery matter, attended with intolerable itching and burning, and lasting several days.-R. copallina is abundant in sandy soil, in many parts of the Middle and Southern States. It is easily distinguished by the leafy expansion on each side of the common petiole. The flowers are greenish-yellow, and are disposed in panicles at the extremities of the branch es-R. radicans, often called, in this country poison ivy, is a climbing, woody vine, which adheres to the trunks and branches of trees, by means of root-like suckers.

The leaves are ternate, and the flowers are disposed in little axillary racemes. It is common in the Northern and Middle States, and affects certain individuals in the same manner as the poison sumach; but it seems to be less virulent, and fewer persons are exposed to its influence.-R. aromatica differs widely in habit from the others. It is a small shrub, with ternate leaves, having the flowers disposed in aments, which grows chiefly on the Alleghanies, and in the Western States. The berries are hairy and red. The celebrated Japan varnish is obtained from a species of rhus, which was formerly considered identical with our poison sumach; but now is recognised as a distinct species, having the under surface of the leaves downy and velvety. This varnish oozes from the tree, on its being wounded, and grows thick and black when exposed to the air. It is so transparent, that when laid pure and unmixed upon boxes or furniture, every vein of the wood may be clearly seen. With it the Japanese varnish over the posts of their doors and windows, their drawers, chests, boxes, cimeters, fans, tea-cups, soup-dishes, and most articles of household furniture made of wood.

SUMAROKOFF, Alexander Petrowitsch, a distinguished Russian tragic poet, who formed himself on French models, was born in 1718, and died at Moscow in 1777. His tragedies, in point of harmony, taste, and purity of style, are compared to those of Racine, though inferior in poetical inspiration. His principal works are Sineus and Truwor (which appeared in 1755), Semire, Jaropolkund Deinise, Korew and Aristone; all of which were translated into French in 1801. Hamlet, Ritschelas, and the Pseudo-Demetrius. The last is considered his best work (translated into French in 1800, also into English). Sumarokoff also wrote comedies, fables and epigrams.

He also wrote

SUMATRA ; an island in the eastern seas, the largest and most westerly of the Sunda islands, separated from the continent by the straits of Malacca, and from Java by the straits of Sunda. It is divided obliquely by the equator into almost equal parts, and its general direction is from N. W. to S. E.; lat. of one extremity 5°56′ N., of the other 5° 56' S. It is about 1000 miles long, and 165, on an average, broad; square miles, about 160,000. A chain of high mountains runs through the whole extent of the island, and the ranges are, in many parts, double and treble. Mount Ophir, immediately under the equinoctial

line, is supposed to be the highest visible from the sea, its summit being elevated 13,842 feet above that level. Among the ridges of mountains are extensive plains of great elevation, and of temperate climate, the most valuable and best inhabited portion of the island. Here, too, are found many large and beautiful lakes, The ridges of mountains lie towards the western shore; in consequence, all the greatest rivers are found on the eastern side. The climate varies with the height of the ground; but on the plains, the heat is not so great as might be expected from the position; the thermometer, in the greatest heat, about two o'clock P. M., generally fluctuating from 82° to 85°: at sunrise, it is usually as low as 70°. The soil is generally fertile; the population for the most part thin; and a great portion of the island is covered with an impenetrable forest. The most important article of cultivation is rice, of which there are many different species. Of articles of commerce, the most abundant is pepper, formerly obtained in greater quantities than at present. Other productions are, gumbenzoin, camphor, cassia, cotton, coffee, &c. The upas (q. v.) tree, and the gigantic rafflesia (q. v.), are among the vegetable curiosities. It is rich in mineral and fossil productions; has long been famous for gold, which is still procured in considerable quantities; and has mines of iron, copper, and tin. It produces a great variety and abundance of fruits, and wild animals, as elephants, tigers, rhinoceroses, alligators, &c.; also birds of various kinds. The inhabitants are rather below the middle size: their limbs are for the most part slight, but well shaped. The women flatten the noses and compress the skulls of children newly born; and the males destroy their beards. The inhabitants have made but little progress, generally, in the arts of industry, though they excel in some particular manufactures. The Malay language is every where spoken along the coasts of Sumatra. (See Malays.) Among the modern political divisions of the island, the principal are the empire of Menancabow and the Malays, the Achineese (see Acheen), the Battas (q. v.), the Rejangs, and the people of Lampong. The Dutch first began to form settlements on the coasts in 1666, and in 1685, the English also established themselves at Bencoolen. (q. v.) In 1825, the presidency of Bencoolen, of which the capital was Fort Marlborough, was ceded to the Dutch, in return for Malacca. (q. v.) The latter were already in possession of Pa

dang, a strong fortress on the western coast, and of Palembang (25,000 inhabitants), on the eastern coast. Previous to the late revolution in the Netherlands, they were making preparations to reduce the whole island. Sir Thomas Stamford Raffles (q. v.) was the first European who penetrated to the interior of the island, which he crossed from Bencoolen to Palembang. See Marsden's History of Sumatra, and Anderson's Mission on the East Coast of Sumatra (Edinb., 1826, 2 vols.).

The

SUMMER; in the northern hemisphere, the season comprehended in the months of June, July, and August; the warmest period of the year. South of the equator, the summer corresponds, in time, to our winter. The entire year is also sometimes divided into the summer, or warm season, and the winter, or cold season. astronomical summer begins, in the northern hemisphere, when the sun has reached its greatest northern elevation,— therefore about June 21,—and ends when it crosses the equator the second time in the year, about September 23. Notwithstanding the changes in the signs of the ecliptic, produced by the precession (q. v.) of the equinoxes, the ancient signs of summer have remained in the calendar. In the northern hemisphere, they are Cancer, Leo, Virgo; in the southern, Capricorn, Aquarius, Pisces. Our summer takes place at the time when the earth is at the greatest distance from the sun, and hence moves the slowest. The diameter of the sun, therefore, appears considerably smaller at this season than in winter, and the summer of the northern hemisphere has ninety-three and a half days, a few days more than the winter,and, therefore, more than the summer of the southern hemisphere. Notwithstanding the greater distance of the sun in summer, his rays have much more effect than in winter, because they fall more directly upon the northern hemisphere. He also rises much sooner, and sets much later, and, therefore, describes a much greater arc in the heavens than in winter. At the time when he has reached the tropic of Cancer, he ascends highest in the heavens, and remains longest above the horizon; and we might, therefore, suppose that this would be the period of the greatest heat. But experience shows that the greatest heat generally takes place in August, throughout the whole northern hemisphere, far beyond the polar circle. The reason of this circumstance is, that, in August, the influence

of the sun's rays has been felt for a long time on the earth, and that, within the polar circle, as far as to the tenth or twelfth degree from the pole, the ice has been thawed and the temperature of the air moderated; hence the wind which blows from those northern regions to the south is milder.-See Meyer's Manual of Physical Astronomy, Theory of the Earth, and Meteorology (German, Göttingen, 1805).

SUMTER, Thomas, a distinguished partisan officer, during the American revolutionary war, died June 1, 1832, at his residence, near the Bradford springs, South Carolina, after a short illness, in the ninety-eighth year of his age. In the commencement of his military career, he was severely tried by adversity, and acquired such circumspection and prudence, that the enterprises which he subsequently conducted were, for the most part, crowned with brilliant success. He gave the first check to the success of the British in South Carolina, after the fall of Charleston, in 1780. The affairs of the state then wore the most gloomy aspect; the citizens were in the deepest despondency, and had abandoned all hope of further resistance, when colonel Sumter, at the head of a small band of followers, who had been forced to retreat, returned to the state, raised again the standard of opposition, and revived and maintained the spirits of the people by a series of gallant achievements. He first routed, July 12, 1780, at Williams's plantation, a marauding detachment of the enemy's army, commanded by captain Huck, a miscreant who had excited universal abhorrence by his cruelty and profanity. In the same month, he made attacks on the posts of Rocky mount and Hanging rock, the first of which was completely successful, as would have been the second, also, could he have restrained the insubordination of his troops, and destroyed their avidity for plunder and liquor. He destroyed, however, the prince of Wales's regiment. Soon after, he captured a convoy of stores passing from Ninety-Six to Camden; but, unfortunately, encamping within striking distance of the enemy, he was surprised by Tarleton, and routed, with the loss of many men and all the prisoners and stores that had recently fallen into his hands. He was next attacked near Broad river by Wennyss, who was repulsed, and he himself wounded and taken. Major Garden, in his Anecdotes of the Revolution, states, that lord Cornwallis wrote,

immediately after this, to Tarleton, "I shall be glad to hear that Sumter is in no condition to give us further trouble; he certainly has been our greatest plague in this country." He was accordingly attacked by Tarleton, in his strong position on Blackstock hill, with the usual impetuosity of that officer, who, however, was compelled to retreat, with a severe loss, leaving his wounded to the mercy of the victor. In this action, Sumter received a severe wound, which, for a considerable time, arrested his career; but he was no sooner able to take the field, than he again appeared as an active partisan, breaking up the British posts in the lower country. About this period, he was promoted to the rank of brigadier-general. On one occasion, lieutenant-colonel Hampton, commanding under him, dispersed a large body of tories, near Dorchester. Placed at the head of the light troops, both regulars and militia, Sumter next compelled lieutenant-colonel Coats to destroy his stores, at Monk's corner, and abandon his position. Important services were again performed by Sumter at Eutaw, after which, the enemy, retiring within their lines, seldom ventured beyond the gates of Charleston. General Sumter was for a long time a member of the American congress, first as a representative, and then a senator, and enjoyed the highest respect. He is thus described in Lee's Memoirs :-"Sumter was younger than Marion, who was about forty-eight years of age, larger in frame, better fitted, in strength of body, to the toils of war, and, like his compeer, devoted to the freedom of his country. His aspect was manly and stern, denoting insuperable firinness and lofty courage. Determined to deserve success, he risked his own life and the lives of his associates without

reserve."

SUN. This magnificent luminary, the great source of light, heat, and life, appears to us a circular and resplendent disk; from which appearance, and the observation of the solar spots (described below), it follows that this body has a form nearly spherical, and turns round its axis once in about twenty-five and a half days, because a sphere only can appear to the eye like a circular disk in all positions. The true relation of the sun, not only to our earth, but to all the planets of our system, has been known since the discoveries of Kepler. The primary planets, accompanied by their moons, revolve about the sun in elliptical orbits, which have but little eccentricity the sun itself

being situated in a focus common to all these ellipses. His mean distance from the earth, which has been finally determined, with tolerable accuracy, by the observation of his parallax (see the subsequent part of this article), amounts, in round numbers, to about 95,000,000 miles: the sun, therefore, is above 400 times farther distant from us than the moon; and a cannon ball which moves 600 feet in each second, would require about 26 years to reach it. The apparent diameter of the sun is pretty nearly the same as that of the moon: it is somewhat above half a degree; yet, according to the various points of the earth's orbit, from which we observe the same, varies somewhat-a necessary consequence of the elliptical form of this orbit. The conclusions which we draw from the differences in the apparent magnitude of the sun as to the different distances of this body from the earth, agree perfectly with what we learn, respecting the same subject, from other sources; so that this point may be considered as well settled. The mass of the sun, which exceeds that of all the planets together 800 times, is, in proportion to that of our earth, according to Piazzi,as 329,630 to 1; the diameter exceeds that of the earth 112 times, the surface 12,700 times, the solid contents 1,435,000 times. The earth appears, as Biot says, by this statement, a mere grain of sand, compared to the sun, which, again, in his turn, is but a point in infinite space. Respecting the physical structure of the sun, astronomers have entertained different opinions, from times immemorial. The hypothesis of Herschel is, that the sun is an opaque body, having on its surface mountains and valleys, like the earth, the whole surrounded by an atmosphere constantly filled with luminous clouds. These sometimes open in particular places, and allow the body of the sun to be seen; hence the appearance of solar spots. This hypothesis seems to be preferable to that of Laplace (who imagines the sun to be a burning body), because it allows us to conceive that the sun is inhabited, which better agrees with the wise use made of space by a beneficent Omnipotence.

Parallax of the Sun.-Parallax and horizontal parallax have been explained in the article Parallax. The horizontal parallax of the sun has been known with greater accuracy since the transit of Venus over the sun's disk in 1761 and 1769. As the orbit of the earth includes that of Venus, the latter must sometimes appear between us and the sun. The duration

of such a transit for the centre of the earth may be calculated; and on comparing this with the duration actually observed on the surface of the earth, the difference of the two results enables us to deduce the horizontal parallax of the sun, and hence the distance of the two luminaries from each other. In this way the mean horizontal parallax of the sun has been estimated by Duréjour at 88", and by Biot at 8' 7", which makes the mean distance of the sun from the earth amount to 23,439 times the radius of the earth (which is about 4000 miles in length), or, in round numbers, 94,000,000 miles. If this horizontal parallax is taken but one tenth of a second smaller, we must add to this distance an amount equal to 215 times the radius of the earth, which explains the difference in the statements of the distance. This distance having been ascertained with tolerable accuracy, we possess the measure of our whole planetary system, as, according to the second law of Kepler (q. v.), the cubes of the mean distances of the planets from the sun are as the squares of the periods of their revolutions (which have long been known). Therefore the determining of this distance is of the highest importance. Respecting the transit of Venus, see Lalande's Astronomie, Enke's Distance of the Sun from the Earth, by the Transit of Venus in 1761, and the Transit of Ve nus in 1769 (in German). (See Transit.)

Spots on the Sun.-Spots of irregular form are often observed in the disk of the sun (q. v.), in greater or less number. They appear in the centre dark, and towards the margin have a whitish-gray umbra, which, however, is often observed spreading over large surfaces, without that black centre. They originate and disappear, sometimes quickly, and without apparent cause, in the middle of the disk; but more frequently are observed to rise on the eastern margin, and move towards the western, where, thirteen days after being first seen, they disappear, and again appear on the eastern margin after a little longer period. The spots appear to revolve round the sun in about twentyseven days. At particular seasons, they move over the sun in straight lines; at all other times, in lines more or less curved; and the paths described by different spots observed at the same time are always parallel to each other, and always have their curvature and position determined by the season. They appear broadest when near the middle point of their passage. All this is satisfactorily explained, if the