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grees and minutes, answering to the angle which every rhumb makes with the meridian, be transferred from its respective line to that which is to be divided, we shall have the several points required: thus, if the distance between the radius or centre and sine of 45 degrees equals the fourth rhumb, be set off upon the line sine of the rhumb, we shall have the point answering to the sine of the fourth rhumb; and after the same manner may both these lines be constructed. The line of meridional parts is construct. ed from the table of meridional parts, in the same manner as the line of numbers is from the logarithms.

The lines being thus constructed, all problems relating to arithmetic, trigonometry, and their depending sciences, may be solved by the extent of the compasses only; and, as all questions are reducible to proportions, the general rule is, to extend the compasses from the first term to the second, and the same extent of the compasses will reach from the third to the fourth; which fourth term must be so continued as to be the thing required, which a little practice will render easy.

SCALE, scala, in music, is a denomination given to the arrangement of the six syllables invented by Guido Aretine, ut, re, mi, fa, sol, la, called also gamut. It bears the name scale (q. d. ladder) because it represents a kind of ladder, by means whereof the voice rises to acute, or descends to grave; each of six syllables being, as it were, one step of the ladder. Scale is also used for a series of sounds rising or falling towards acuteness or gravity, from any given pitch of tune, to the greatest distance that is fit or practicable, through such intermediate degrees as make the succession most agreeable and perfect, and in which we have all the harmonical intervals most commodiously divided.

SCALES of fish, generally possess a silvery whiteness, and are composed of different laminæ. In many of their properties they resemble horn. By long boiling in water they become soft, and when they are kept for some hours in nitric acid, they are converted into a transparent membranous substance. By saturating the acid with ammonia, a precipitate is formed, which is phosphate of lime. The constituent parts of scales, therefore, are membrane and phosphate of lime.

SCALENE, or SCALENOUS TRIANGLE,

in geometry, a triangle whose sides and angles are unequal.

SCAMMONY, in the Materia Medica, is a concreted vegetable juice of a plant of the same name, partly of the resin and partly of the gum kind, of which there are two sorts, distinguished by the names of the places from whence they are brought. The Aleppo scammony is of a spongy texture, light and friable; it is of a faint disagreeable smell, and its taste is bitterish, very nauseous, and acrimonious. The Smyrna scammony is considerably hard and heavy, of a black colour, and of a much stronger smell and taste than the former, otherwise it much resembles it.

SCANDALUM magnatum, is the special name of a statute, and also of a wrong done to any high personage of the land, as prelates, dukes, marquises, earls, barons, and other nobles; and also the chancellor, treasurer, clerk of the privy seal, steward of the house, justice of one bench or other, and other great officers of the realm, by false news, or horrible or false messages, whereby debates and discord, between them and the commons, or any scandal to their persons, might arise. 2 Richard II. c. 5. This statute has given a name to a writ, granted to recover damages thereupon.

It is now clearly agreed, that though there be no express words in the statute which give an action, yet the party injur ed may maintain one on this principle of law, that when a statute prohibits the doing of a thing, which, if done, might be prejudicial to another, in such case he may have an action on that very statute for his damages.

SCANDIX, in botany, chervil, a genus of the Pentandria Digynia class and order. Natural order of Umbellatæ or Umbelliferæ. Essential character: florets of the disk most commonly male; corolla radiate; petals emarginate; fruit awl-shaped. There are eleven species. The most remarkable is S. odorata, with angular furrowed seeds. It is a native of Germany, and has a very thick perennial root, composed of many fibres, of a sweet aromatic taste, like aniseed, from which come forth many large leaves that branch out somewhat like those of fern, whence it is named sweet fern.

SCANNING, in poetry, the measuring of a verse by feet, in order to see whether or no the quantities be duly observed.

The term is chiefly used in regard to the Greek and Latin verses. Thus an

hexameter verse is scanned, by resolving it into six feet; a pentameter, by resolv ing it into five feet, &c.

SCANTLING, in building, is particuTarly applied to the dimensions of any piece of timber, with regard to its breadth and thickness.

SCAPEMENT, a general term for the manner of communicating the impulse of the wheels to the pendulum of a clock. Common scapements consist of the swing wheel and pallets only. See HoROLOGY, &c.

SCAPOLITE, in mineralogy, a species of the Flint genus, is of a greyish white colour, passing into greenish grey; it occurs massive, but most commonly crystallized in long, thin, often acicular prisms. Externally it is glistening; internally it is shining and glistening; its lustre is between resinous and pearly. It is brittle and frangible. Specific gravity about 3.7. Before the blow-pipe it intumesces, and melts into shining white enamel. It is found in the iron-stone mines in Norway. Its crystals are sometimes mixed with mica, calc-spar, and felspar. It is composed of

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SCARABEUS, in natural history, the beetle, a genus of insects of the order Coleoptera. Generic character: antennæ clavate, the club lamellate; feelers four; fore-shanks generally toothed. In this genus there are several hundred species, in four divisions, which are distinguished by the form of their feelers.

S. Hercules, or Hercules beetle, is the most remarkable species, as well in size as in beauty. It is five or six inches long; the wing-shells are of a smooth surface, of a bluish-grey colour, marked with round, deep-black spots, of different sizes; from the upper part of the thorax proceeds a horn of great length in proportion to the body; it is sharp at the tip, and is furnished, throughout its whole length with a fine, short, velvet-like pile, of a brownish-orange colour; from the front of the head also proceeds a strong

VOL. XI.

horn, like the other, but not furnished with any pile. This insect is found in several parts of South America, where great numbers are said to be sometimes seen on the mammee-tree, rasping off the rind of the slender branches, by working nimbly round them with the horns, till they cause the juice to flow, which they drink to intoxication, and in this state fall senseless from the tree. This fact has been controverted by the learned Fabricius.

In this country, the S. melolontha, or cock-chaffer, is very common. The larva inhabits ploughed lands, and feeding on the roots of corn; and the complete insect makes its appearance during the middle and the decline of summer. This insect sometimes appears in such prodigious numbers, as almost to strip the trees of their foliage, and to produce mischiefs nearly approaching to those of the locust-tribe; they are thus described in the "Philosophical Transactions" for the year 1697, by Mr. Molineux. "These insects were first noticed in this kingdom in 1688. They appeared on the southwest coast of Galway, brought thither by a south-west wind, one of the most common, I might almost say, trade-winds of this country. From hence they penetrat ed into the inland parts towards Heddford, about twelve miles north of the town of Galway: here and there, in the adjacent country, multitudes of them appeared among the trees and hedges, in the day time, hanging by the boughs in clusters, like bees when they swarm. In this posture they continued, with little or no motion, during the heat of the sun; but towards evening or sun-set, they would all disperse and fly about, with a strange humming noise, like the beating of distant drums, and in such vast numbers, that they darkened the air for the space of two or three miles square. Persons travelling on the roads, or abroad in the fields, found it very uneasy to make their way through them, they would so beat and knock themselves against their faces in their flight, and with such a force as to make the place smart, and leave a slight mark behind them. In a short time after their coming, they had so entirely eaten up and destroyed all the leaves of the trees, for some miles round, that the whole country, though in the middle of summer, was left as bare as in the depth of winter: and the noise they made in gnawing the leaves, made a sound much resembling the sawing of timber. They also came into the gardens, and destroyed

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the buds, blossoms, and leaves of all the fruit-trees, so that they were left perfect ly naked, nay many, that were more delicate than the rest, lost their sap, as well as leaves, and quite withered away, so that they never recovered again. Their multitudes spread so exceedingly, that they infested houses, and became extremely offensive and troublesome. Their numerous young, hatched from the eggs which they had lodged under ground, near the surface of the earth, did still more harm in that close retirement than all the flying swarms of their parents had done abroad; for this destructive brood, lying under ground, eat up the roots of corn and grass, and thus consumed the support both of man and beast. This plague was happily checked several ways. High winds, and wet misling weather, destroyed many millions of them in a day; and when this constitution of the air prevailed, they were so enfeebled that they would let go their hold, and drop to the ground, from the branches, and so little a fall as this was sufficient quite to disa ble, and sometimes perfectly kill them. Nay, it was observable, that even when they were most vigorous, a slight blow would for some time stun them, if not deprive them of life. During these unfavourable seasons of the weather, the swine and poultry of the country would watch under the trees for their falling, and feed and fatten upon them; and even the poorer sort of the country people, the country then labouring under a scarcity of provision, had a way of dressing them, and lived upon them as food. In a little time it was found, that smoke was another thing very offensive to them, and by burning heath, fern, &c. the gardens were secured, or, if the insects had already entered, they were thus driven out again. Towards the latter end of summer, they returned of themselves, and so totally disappeared, that in a few days you could not see one left. A year or two ago, all along the south-west coast of the county of Galway, for some miles together, there were found dead on the shore such infinite multitudes of them, and in such vast heaps, that, by a moderate estimate, it was computed there could not be less than forty or fifty horse loads in all; which was a new colony, or a supernumerary swarm, from the same place whence the first stock came in 1688, driven by the wind from their native land, which I conclude to be Normandy, or Brittany, in France, it being a country much infested with this insect, and from

whence England heretofore has been pestered in a similar manner with swarms of this vermin; but these, meeting with a contrary wind before they could land, were stopped, and, tired with the voyage, were all driven into the sea, which, by the motion of its waves and tides, cast their floating bodies in heaps on the shore. It is observed that they seldom keep above a year together in a place, and their usual stages, or marches, are computed to be about six miles in a year. Hitherto their progress has been westerly, following the course of that wind, which blows most commonly in this country."

The larva of this insect is eagerly sought after and devoured by swine, bats, crows, and poultry: it is said to be two or three years in passing from its first form into that of the perfect insect. The eggs are laid in small detached heaps, beneath the surface of some clod, and the young, when first hatched, are scarcely more than the eighth of an inch in length, gradually advancing in their growth, and occasionally shifting their skins, till they arrive at the length of nearly two inches. At this period they begin to prepare for their change into a chrysalis or pupa, selecting for the purpose some small clod of earth, in which they form a cavity, and after a certain time, divest themselves of their last skin, and immediately appear in the pupa state. In this they continue till the succeeding summer, when the beetle emerges from its retirement, and commits its depredations on the leaves of trees, breeds, and deposits its eggs in a favourable situation, after which its life is of very short duration.— If the larva appear in autumn in considerable quantities, they are said to prognosticate epidemic disorders.

A species of great beauty is the S. auratus, or golden beetle, about the size of the common or black garden beetle: the colour is most brilliant, varnished, and of a golden-green. This is a fine object for the magnifying glass. It is not very uncommon during the hottest parts of summer, frequenting various plants and flowers; its larva is commonly found in the hollows of old trees, or among the loose dry soil at their roots, and sometimes in the earth of ant-hills.

Mr. Donovan has described, among his English insects, the S. stercorarius, or clock-beetle, which flies about in an evening, in a circular direction, with a loud buzzing noise, and is said to foretel a fine day. It was consecrated by the Egyp

tians to the sun; is infested with the acarus and Ichneumon; the body is often coloured with a bluish or greenish gloss, sometimes brassy beneath; shells frequently dull, rufous.

SCARIFICATION, in surgery, the operation of making several incisions in the skin by means of lancets, or other instruments, particularly the cupping instru

ment.

SCARP, in fortification, is the interior talus, or slope of the ditch next the place, at the foot of the rampart.

SCARP, in heraldry, the scarf which military commanders wear for ornament. It is borne somewhat like a battoon sinister, but is broader than it, and is continued out to the edges of the field; whereas the battoon is cut off at each end.

SCARUS, in natural history, a genus of fishes of the order Thoracici. Generic character: instead of teeth, strong bony processes, crenated at the edges: gillmembrane five-rayed; lateral line mostly branched. There are eight species; S. rivulatus, is found in the Red Sea, about the length of three feet. It feeds on herbs, and is used for food; but any puncture, or laceration, by the dorsal spine of this fish, is said to be attended with extraordinary pain and inflammation. The other species are mostly inhabitants of the same

sea.

SCAVAGE, a toll or custom anciently exacted by mayors, sheriffs, and bailiffs, of cities and towns corporate, and of merchant-strangers, for wares exposed and offered to sale within their liberties; which was prohibited by 19 Henry VII. But the City of London still retains this

custom.

SCENOGRAPHY, in perspective, the representation of a body on a perspective plane; or, a description thereof in all its dimensions, such as it appears to the eye. The ichnography of a building, &c. represents its plan, or ground-work; the orthography is a view of the front, or one of its sides; and the scenography is a view of the whole building, front, sides, height, and all, raised on the geometrical plan

SCEPTRE, in astronomy, one of the six new constellations of the southern hemisphere, consisting of seventeen stars. SCHAALSTONE, in mineralogy, a species of the calc genus, is of a greyish white colour, with varieties; it occurs massive, and the lustre of its principal fracture is shining and nearly pearly. It is translucent, brittle, easily frangible, and not very heavy. It has hitherto been found only in the Bannat of Temeswar,

and is accompanied by ores of copper. It is composed of lime and silica.

SCHAUM earth, or FOAMING earth, in mineralogy, a species of the calc genus, is of a very light yellowish, nearly silver white colour, approaching sometimes to greyish-white. It occurs massive and disseminated, sometimes loose, and composed of fine scaly particles, or internediate between friable and loose. Its lustre is between shining and glistening. It is soft, friable, fine, but not greasy. With acids it effervesces, and is dissolved in them. By analysis it is found to be composed of lime and carbonic acid. It is nearly allied to slate-spar, and is found in the forest of Thuringia, also in the north of Ireland.

SCHEFFLERA, in botany, so named in honour of Scheffer, physician and botanist at Dantzic, a genus of the Pentandria Decagynia class and order. Essential character: calyx five-toothed; corolla fivepetalled; capsule eight or ten celled; seeds solitary, semicircular. There is only one species, viz. S. digitata, a native of New Zealand.

SCHEME, a draught or representation of any astronomical or geometrical figure or problem, by lines sensible to the eye; or of the celestial bodies in their proper places for any given moment. It is otherwise called a diagram.

SCHEUCHZERIA, in botany, so named in memory of John Scheuchzer, professor of physic at Zurich, a genus of the Hexandra Trigynia class and order. Natural order of Tripetaloideæ. Junci, Jussieu. Essential character: calyx six-parted; corolla none; styles none; capsule three, inflated, one-seeded. There is but one species, viz. S. palustris, a native of the North of Europe.

SCHIEFER spar, one of the species of carbonate of lime. It is of a grey colour, passing to red, and even in some specimens to green. It is found massive,; the texture is foliated; it is brittle; feels unctuous; and may be scratched with the nail. Specific gravity 2.7. It is composed of carbonate of lime, with some silica, and oxide of iron.

SCHILLER stone, in mineralogy, a species of the talc genus, of an olive green; usually disseminated and massive, probably also crystallized. Lustre shining, passing into semi-metallic: fracture perfectly foliate. Soft, slightly brittle, easi ly frangible, and not particularly heavy. It occurs imbedded in serpentine, and is frequently accompanied with mica. It is found in Saxony, Cornwall and Scotland.

SCHINUS, in botany, a genus of the Dioecia Decandria class and order. Natural order of Dumosæ Terebintaceæ, Jussieu. Essential character: calyx fiveparted; petals five: female, berry threecelled. There are two species, viz S. molle, Peruvian mastich tree, and S. areira, Brazilian mastich tree.

SCHISTUS, in mineralogy, a name given to several different kinds of stones, but more especially to some of the argillaceous kind: as, 1. The bluish purple schistus, S. tegularis, or common roof-slate: this is so soft that it may be slightly scraped with the nail, and is of a very brittle lamellated texture of the specific gravity of 28. It is fusible per se in a strong heat, and runs into a black scoria. By a chemical analysis it is found to consist of Argillaceous earth 26 Silex Magnesia

Lime

Iron

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The dark blue slate, or S. scriptorius, contains more magnesia and less iron than the common purple schistus, and effervesces more briskly with acids. Its specific gravity is 27. 2. The pyritaceous schistus is of a grey colour, brown, blue, or black; and capable of more or less decomposition by exposure to the air, according to the quantity of pyritous matter it contains, and the state of the iron in it. The aluminous schistus belongs to this species. 3 The bituminous schistus is generally black, and of a lamellated texture, of various degrees of hardness, not giving fire with steel, but emitting a strong smell when heated, and sometimes without being heated.

SCHMELZSTEIN, in mineralogy, a substance, hitherto only found on the Pyrenees, where it is imbedded in steatite: it is of a greyish white, passing through the different shades to "ose red; it is shining, and its lustre is vitreous; it is easily frangible. Specific gravity 26. It swells before the blow-pipe. The constituent parts are

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SCHMIDELIA, in botany, so named in honour of Casimir Christopher Schmidel, professor of botany at Erlang, a genus of the Octandria Digynia class and order. Natural order of Sapindi, Jussieu. Essential character: calyx two-leaved; corolla four-petalled; germs pedicelled, longer than the flower. There is only one species, viz. S. racemosa, a native of the East Indies.

SCHOENUS, in botany, bog rush, a ge. nus of the Triandria Monogynia class and order. Natural order of Calamariæ. Cyperoideæ, Jussieu. Essential character; glumes chaffy, heaped, the outer ones barren; corolla none; seed one, roundish among the glumes. There are forty-one species.

SCHOEPFIA, in botany, so named in honour of Johan David Schoepf, a genus of the Pentandria Monogynia class and order Natural order of Aggregatæ. Caprifolia, Jussieu Essential character: Calyx double, outer bifid, inferior; inner superior, quite entire; corolla bell-shaped; stigma capitate; drupe one-seeded. There is but one species, viz. S. Americana, a native of Santa Cruz and Montserrat.

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SCHOLIAST, or CoMMENTATOR, grammarian, who writes scholia, that is, notes, glosses, &c. upon ancient authors, who have written in the learned languages. See the next article.

SCHOLIUM, a note, annotation, or remark, occasionally made on some passage, proposition, or the like. This term is much used in geometry, and other parts of mathematics, where, after demonstrating a proposition, it is customary to point out how it might be done some other way, or to give some advice, or precaution, in order to prevent mistakes, or add some particular use, or application thereof.

SCHORL, in mineralogy, a species of the Flint genus, which is divided by Werschorl and the tourmaline. The common ner into two sub-species, viz. the common schorl is black. It occurs often massive and disseminated, seldom in rolled pieThe ces, and frequently crystallized. crystals are mostly acicular; fragments, when broken, indeterminably angular; it very rarely presents coarse and small grained distinct concretions; sometimes it occurs in very thin, and but rarely in thick, straight and prismatic distinct concretions. It is opaque, and but little translucent on the edges, when it passes to the tourmaline. It gives a grey streak; is hard, and very easily frangible. Specific gravity from 3.09 to 3.21. It melts before

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