with a blue interior circle and a black centre. This insect proceeds from a green caterpillar, of a rough or shagreenlike surface, marked on each side by seven oblique yellowish-white streaks, and furnished, like the preceding, with a horn at the tail. It is principally found on the willow; retires under ground, in order to undergo its change into the chrysalis state, in the month of August or September; and in the following June appears the complete insect.

SPICA, in botany, a term applied to a particular mode of flowering, in which the flowers are ranged alternately upon both sides of a simple common flower-stalk. The flowers in the spica are seated immediately upon the stalk, without any partial foot-stalk, in which it differs from a racemus, or cluster. A spica is said to be single rowed when the flowers are all turned towards one side; and to be double rowed when they look to both sides, or stand two ways.

SPIDER. See ARANEA. SPIELMANNIA, in botany, so named in honour of James Reinbold Spielmann, a genus of the Didynamia Angiospermia class and order. Natural order of Personatæ. Vitices, Jussieu. Essential character: calyx five-cleft; corolla bearded at the throat, with a five-cleft almost equal border; drupe with a two-celled, two seeded nut. There is only one species, viz. S. Africana, silex leaved Spielmannia, or lantana, a native of the Cape of Good Hope.

SPIGELIA, in botany, so named in memory of Adrian Spigelius, a genus of the Pentandria Monogynia class and order. Natural order of Stellatæ. Gentianæ, Jussieu. Essential character: corolla funnel shaped; capsule twin, two-celled, many seeded. There are two species, viz. S. anthelmia, annual worm-grass; and S. marilandica, perennial worm-grass.

SPIKING up the ordnance, a sea phrase, used for fastening a quoin with spikes to the deck close to the breech of the carriages of great guns, that they may keep close and firm to the ship's sides, and not get loose when the ship rolls, and by that means endanger the breaking out of a butt head of a blank.

SPILANTHUS, in botany, a genus of the Syngenesia Polygamia Equalis class and order. Natural order of Compositæ Oppositifolia. Corymbiferæ, Jussieu. Essential character: calyx almost equal; down two-toothed; receptacle conical, chaffy. There are nine species. This genus is made up chiefly of those species

of bidens and verbesina which do not properly belong to those genera; they are natives of the East and West Indies.

SPINA, in botany, a thorn, a species of offensive weapon, protruded from the wood of the plant, and which is therefore of a stronger and harder nature than prickles, which are detached portions of the bark. Thorns, which are an expansion of the ligneous body, are compared to the horns of animals, which adhere to the bones of the skull, and are protruded from them.

SPINACIA, in botany, spinach, a genus of the Dioecia Pentandria class and order. Natural order of Holoraceæ. Atriplices, Jussieu. Essential character: male, calyx five parted; corolla none : female, calyx four-cleft; corolla none : styles four; seed one, within the hardened calyx. There are two species: viz. S. oleracea, garden spinach; and S. fera, wild spinach. There are also two varieties.

SPINDLE, in the sea language, is the smallest part of the ship's capstan, which is between the two decks. The spindle of the jeer-capstan has whelps to heave the viol. The axis of the wheel of a watch or clock is also called the spindle. Among miners, the spindle is a piece of wood fastened into either stow blade.

SPINELLE, in mineralogy, a species of the flint genus: its principal colour is red, from which it passes on the one side into blue, and even into green, on the other into yellow and brown. Its colours are mostly deep, and they have always a shade of black. Sometimes it is enveloped in an opaline crust; sometimes it exhibits an opalescent iridescence. It occurs in grains, which, from their aspect, show that they have been rolled, and also crystallized. Its specific gravity is from 3.5 to 3.7. It is unalterable before the blow-pipe without addition; but is fusible with borax: it consists, according to Klaproth, of

as a precious stone, and is of considerable value; but it is not so hightly esteemed as the oriental ruby: from this it is distinguished by being harder, and of a greater specific gravity.

SPINET, or SPINNET, a musical instrument, ranked in the second or third place among harmonious instruments. See MuSICAL Instruments.

SPINIFEX, in botany, a genus of the Polygamia Dioecia class and order. Natural order of Gramina, Gramineæ, or Grasses. Essential character: hermaphrodite; calyx glume two-valved, two-flowered; valves parallel to the rachis; corolla twovalved, awnless; stamens three; styles two: male, calyx common with the hermaphrodite; corolla and stamens similar. There is only one species; viz. S. squarrosus, a native of the East Indies, China, and Cochin China, on sandy coasts.

SPINNING, the act of reducing silk, flax, hemp, hair, wool, or other matter, into thread. Spinning is either performed on the wheel, or with a distaff and spindle, or with other machines proper for the several kinds of working. Hemp, flax, nettle-thread, and other like vegetable matters, are to be wetted in spinning: silks, wools, &c. are spun dry, at least they do not stand in need of water: there is, however, a way of spinning or reeling silk as it comes off the cases or balls, where hot, or even boiling water is to be used. The vast variety and importance of these branches of our manufactures, which are produced from cotton, wool, and flax, spun into yarn, together with the cheapness of provisions, and the low price of labour, in many foreign countries, which are the rivals of our trade, have occasioned many attempts at home to render spinning more easy, cheap, and expeditious. Mr. Arkwright has carried the invention to a high degree of perfection. He not only contrived methods for spinning cotton, but obtained a patent for making cotton, flax, and wool, into yarn. See MANUFACTURE of Cotton.

SPINTHERE, in mineralogy, one of the earthy fossils, of a greenish colour: it occurs crystallized, in irregular, double, four-sided pyramids, which are obliquely truncated. The crystals are small, and the fracture foliated. It melts very easily before the blow-pipe.

SPIO, in natural history, a genus of the Vermes Mollusca class and order: body projecting from a tube, jointed, and furnished with dorsal fibres; peduncles, or feet, rough with bristles, and placed

towards the back; feelers two, long, sim ple; two eyes, oblong. There are two species, viz. S. seticornis: feelers thin and striate: is found in the ocean, principally where there is a clayey bottom: it is about three inches long: the tube is composed of agglutinated particles of earth, thin, erect, and thrice as long as the body; from this the animal projects its capillary white feelers in search of food, which consists of small marine worms: body whitish, with a tinge of green, and a red line down the middle of the back; the hind part sea-green; the fore part blackish grey, with transverse white striæ: head pale. The other species is S. filicornis; feelers thick and annulate it inhabits the seas about Greenland; it is about an inch long, and from its tube projects its feelers in search of Planaria, and other small marine

worms.

SPIREA, in botany, a genus of the Icosandria Pentagynia class and order. Natural order of Pomaceæ. Rosacea, Jussieu. Essential character: calyx fivecleft; petals five; capsule many-seeded, There are twenty-two species.

SPIRAL, in geometry, a curve line of the circular kind, which, in its progress, recedes from its centre.

A spiral, according to Archimedes, its inventor, is thus generated: if a right line, as AB, (Plate Miscel. XIV. fig. 9.) having one end fixed at B, be equally moved round, so as with the other end A to describe the periphery of a circle; and, at the same time, a point be conceived to move forward equally from B towards A, in the right line BA, so as that the point describes that line, while the line generates the circle: then will the point, with its two motions, describe the curve line B 1, 2, 3, 4, 5, &c. which is called the helix or spiral line; and the plane space contained between the spiral line and the right line BA is called the spiral space.

If also you conceive the point B to move twice as slow as the line A B, so as that it shall get but half way along the line B A, when that line shall have formed the circle; and if then you imagine a new revolution to be made of the line carrying the point, so that they shall end their motion at last together, there will be formed a double spiral line, and the two spiral spaces, as you see in the figure. From the genesis of this curve, the following corollaries may be easily drawn. 1. The lines B 12, B 11, B 10, &c. making equal

angles with the first and second spiral (as all B 12, B 10, B 8, &c.) are in arithmetical proportion. 2. The lines B 7, B 10, &c. drawn any how to the first spiral, are to one another as the arches of the circle intercepted between B A and those lines. 3. Any lines drawn from B to the second spiral, as B 18, B 22, &c. are to each other as the aforesaid arches, together with the whole periphery added on both sides. 4. The first spiral space is to the first circle as one to 3. And 5. The first spiral line is equal to half the periphery of the first circle; for the radii of the sectors, and consequently the arches, are in a simple arithmetical progression, while the periphery of the circle contains as many arches equal to the greatest; wherefore the periphery to all those arches is to the spiral lines as 2 to 1.

SPIRAL, in architecture and sculpture, implies a curve that ascends, winding about a cone or spire, so as all the points thereof continually approach the axis. It is distinguished from the helix by its winding around a cone, whereas the helix winds in the same manner around a cylinder.

SPIRALS, proportional, are such spiral lines as the rhumb lines on the terrestrial globe, which, because they make equal angles with every meridian, must also make equal angles with the meridians in the stereographic projection on the plane of the equator; and therefore will be, as Dr. Halley observes, proportional spirals about the polar point.

SPIRE, in architecture, was used by the ancients for the base of a column, and sometimes for the astragal, or tore. But, among the moderns, it denotes a steeple that continually diminishes as it ascends, whether conically or pyramidally.

SPLACHNUM, in botany, a genus of the Cryptogamia Musci class and order. Generic character: capsule cylindrical; veil and receptacle very large; fringe with eight teeth. Male, a bud on a different plant; circular, terminating.

SPLEEN, See ANATOMY.

SPLENTS, or SPLINTS, in surgery, pieces of wood, used in binding up broken limbs.

SPLICING, in the sea language, is the untwisting the ends of two cables or ropes, and working the several strands into one another by a fidd, so that they become as strong as if they were but one rope.

SPLINTER, a small shiver of wood, or the like. The splinters of fractured

bones, if loose, are to be carefully removed, otherwise replaced.

SPODUMENE, in mineralogy, one of the earthy fossils, of a greenish-white colour, passing into apple-green. It occurs in small masses, is shining, and of a pearly lustre. Specific gravity about 3.2. It splits before the blow-pipe into smallish yellowish folia, and at length melts into a greyish-white transparent glass. It is found in the mines of Upton, in Sweden, accompanied with quartz and black mica. SPONDEE, spondæus, in ancient poetry, a foot consisting of two long syllables, as

omnes.

Some give the appellation spondaic to verses composed wholly of spondees, or at least that end with two spondees; as,

Constitit, atque oculus Phrygia agmina circumspexit.

SPONDIAS, in botany, hog-plum, a genus of the Decandria Pentagynia class and order. Natural order of Terebintaceæ, Jussieu. Essential character: calyx five-toothed; corolla five-petalled; drupe with a five-celled nut. There are four species.

SPONDYLUS, in natural history, a genus of the Vermes Testacea class and order: animal a tethys: shell, hard, solid, with unequal valves; one of the valves convex, the other rather flat: hinge with two recurved teeth, separated by a small hollow. There are four species: the shell of the S. gædaropus is slightly eared, and spinous: it inhabits the Mediterranean, Indian, and other seas, and is found in almost infinite varieties as to size, thickness, and colours; sometimes entirely purple, orange, white, or bloom colour; sometimes marked with various streaks, spots, dots, or bands.

SPONGIA, in natural history, sponge, a genus of the Vermes Zoophyta class and order: animal fixed, torpid, of various forms, composed either of reticulate fibres, or masses of small spines, interwoven together, and clothed with gelatinous flesh, full of small mouths on its surface, by which it absorbs and rejects water. Between fifty and sixty species have been enumerated. S. officinalis is irregularly formed, porous, tough, lobed, and woolly: It is found in the Archipelago, Mediterranean and Indian seas, adhering to rocks by a broad base it is often found inclosing small stones, shells, and particles of sand: variety of marine animals pierce and gnaw it into irregular winding cavities, which appear on the outside by

large holes higher than the rest: its colour varies from a pale to a deep yellow; the internal part, when cut perpendicular, consists of small tubes, composed of reticulate fibres, and ending on the outside in an infinite number of small circular holes, which are the bibulous mouths of the animal, each of which is surrounded by a few erect pointed fibres. This is the common sponge of the shops.

S. ventilabrum, is fan-shaped, regular, soft, with reticulate woody veins, covered with pores like a honeycomb. This species inhabits the Norway and American seas; is about six inches high, and five broad: exactly resembles a small Gorgonia flabellum in its shape and ramifications, except that the pores are angular, and the substance is spongy.

S. cristata, or cock's-comb sponge, is flat, erect, and soft, growing in the shape of cock's combs, with rows of little holes along the tops, which project a little. It abounds on the rocks to the eastward of Hastings, in Sussex, where it may be seen at low-water. It is commonly about three inches long, and two inches high, and of a pale yellowish colour. When put into a glass vessel of sea water, it has been observed to suck in and squirt out the water through little mouths along the tops, giving evident signs of life.

S. tomentosa, or urens, stinging sponge, or crumb of bread sponge, is of many forms, full of pores, very brittle and soft, and interwoven with very minute spines. It is full of small protuberances, with a hole in each, by which it sucks in and throws out the water. It is very common on the British coast; and is frequently seen surrounding fucuses. It is found also on the shores of North America, Africa, and in the East Indies. When newly taken out of the sea, it is of a bright orange colour, and full of gelatinous flesh; but when dry, it becomes whitish, and when broken has the appearance of crumbs of bread. If rubbed on the band, it will raise blisters; and if dried in an oven, its power of stinging is much increased, especially that variety of it which is found on the sea coast of North America.

S. fluviatilis, river sponge, is green, erect, brittle, and irregularly disposed in numerous branches. It abounds in many parts of Europe, in the fresh rivers of Russia and England, but particularly in the river Thames. It scarcely exhibits any symptoms of life; is of a fishy smell; its pores, or mouths, are sometimes filled with green gelatinous globules.

So early as the days of Aristotle sponges were supposed to possess animal life; the persons employed in collecting them having observed them shrink when torn from the rocks, thus exhibiting symptoms of sensation. The same opinion prevailed in the time of Pliny. But no attention was paid to this subject, till Count Marsigli examined them, and declared them vegetables. Dr. Peysonell, in a paper which he sent to the Royal Society in the year 1752, and in a second in 1757, affirmed they were not vegetables, but the production of animals, and has accordingly described the animals; and the process which they performed in making the sponges. Mr. Ellis, in the year 1762, was at great pains to discover these animals. For this purpose he dissected the spongia urens, and was surprised to find a great number of small worms, of the genus nereis, or sea scolopendra, which had pierced their way through the soft substance of the sponge in quest of a safe retreat. That this was really the case, he was fully assured of, by inspecting a number of specimens of the same sort of sponge, just fresh from the sea. He put them into a glass filled with sea water: and then, instead of seeing any of the little animals which Dr. Peysonell described, he observed the papillæ, or small holes with which the papillæ are surrounded, contract and dilate themselves. amined another variety of the same species of sponge, and plainly perceived the small tubes inspire and expire the water. He therefore concluded, that the sponge is an animal, and that the ends or openings of the branched tubes, are the mouths by which it receives its nourishment, and discharges its excrements.

SPOON-bill. See PLATEA.

He ex

SPOONING, in the sea language, is said of a ship, which, being under sail in a storm at sea, is unable to bear it, and consequently forced to put right before the wind.

SPORTING. Although we have not omitted to notice what generally appertains to the winged, finny, or quadruped parts of nature, it appeared to us better to collect the whole of the matter relating to sporting, in general, under one head; thereby to preclude the necessity for reverting to other volumes for such information as might be sought. The reader will, however, remark, that we have, under the article ANGLING, furnished an ample detail of that diversion: therefore we shall proceed to the discussion of what relates to FOWLING. The

first item presenting itself to our consideration is the gun; which ought always to be suited to the occasion. For ordinary field excurions, that is to say, when quest ing for pheasants, or partridges, the piece ought to be conveniently light, and of rather a small bore; the barrel from two feet four to two feet six, or perhaps eight inches in length. Chambered guns undoubtedly strike hardest, and in most instances will be found to scatter least. Hence a good marksman will prefer such; but taking care to allow full thirty yards distance to the bird, unless in cases of emergency, before the trigger is drawn. When this precaution is neglected, the chance of missing is greater; while, on the other hand, such birds as may be hit are absolutely spoiled by the column of shot which brings them down. The gun requisite for cocking, that is, for wood-cock shooting, is of a very light construction, and very short; because the birds generally rise well within shot, and that the branches of trees, &c. may be less in the way of the gun's motion while taking aim. We have seen some guns made for this branch of shooting that have been little heavier than a large horsepistol. With regard to such birds as are found on plains, or are aquatics, guns of a larger calibre, and more strongly fortified, so as to resist a large charge of powder without recoiling severcly, are indispensably necessary. The selection of a gun, must, after all, depend on various circumstances: for instance, a powerful man, in the prime of life, and of a large stature, would be no ways incommoded by such a one, as would prove highly distressing to an elderly person, of a weak frame, and of a diminutive size. Again, we necessarily make a distinction according to the nature of the sport: hence, when shooting in a punt, or when laying wait for water-fowl, a heavy gun may be used. In truth, without a very strong charge, some of the more shy, or more full feathered, birds are not easily brought down. Some experienced persons find that with a stout barrel, weigh ing from ten to fourteen pounds, they can bear the recoil of even two drachms of powder; which in an ordinary piece would produce, at least, an highly unpleasant recoil, if not some damage to either the piece or the sportsman. Every barrel ought to be chambered; because the piece is thereby strengthened, and the force, or impetus, of the shot considerably increased. With respect to the kind of chamber, a variety of opinions

exist; for the most part purely theoreti> cal, and in support of some favourite hypothesis, started, by way of novelty, by some maker anxious to obtain celebrity. After mature consideration, we are rather disposed to accord with a number of old sportsmen in commending the plain cylindrical chamber, made in the butt screw, or by a very small screw stump added to the butt of the piece: the latter being preferable in respect to security against lodging fire in the worm of the screw; but rather more expensive.

The lock of a gun is a most important object. It cannot well be too small and compact, provided space be allowed for the free movement of the several parts. We all know that the lock of a pistol will answer its purpose as well as that of a musket. The great consideration is, that friction should be avoided by every possible means, which is best effected by the most simple movements, and by keeping them clear from the plates. Every part subject to the action of another should be well steeled and hardened; and, where practicable, friction rollers should be employed. The pan, above all things, ought to shut very close, and to spring up in a smart manner, when struck by the flint. The trigger should not be subject to action at half-cock; but at full-cock ought to draw with little resistance at least, it should not require such force as might derange the aim, or delay the discharge.

Such guns as have double barrels are commonly provided with a trigger for each lock; though some are made with but one trigger. In the former case, either barrel may be discharged at pleasure, which is not always the case in the latter mode of construction; which, though apparently more simple, is by no means so convenient. The alleged reason of having but one is, that the interior is simplified, while the sportsman is less bewildered in regard to the choice of triggers, and in the application of the finger thereto; but we conceive, that no cool or expert sportsman is ever at a loss in those particulars.

We now come to speak of the sizes of shot in ordinary use, as they are appropriated to various kinds and sizes of birds: observing, that many old sportsmen and game-keepers, consider it advantageous to mix No. 4, 5, 6, and 7, in nearly equal quantities. This, however, does not seem to be warranted. The application of particular sizes to corresponding purposes appears to us