SHEET LEAD. See Book II. Chap. III. Sect. 7.

SHELF. (Sax.) A board fixed against a wall by its edge, the upper side being horizontal, for receiving whatever may be placed upon it. A shelf is usually supported by brackets, or by pieces at the end, called standards.

SHINGLES. (Germ. Schindel.) Small oaken boards used like slates for covering a building, from eight to twelve inches long, and about four inches broad, thicker on one edge than the other. The process of making a roof of this kind is called shingling.

SHOE. The inclined piece at the bottom of a water trunk or lead pipe for turning the course of the water, and discharging it from the wall of a building.

SHORE OF SHOAR. (Sax.) A prop or oblique timber acting as a brace on the side of a building, the upper end resting against that part of the wall upon which the floor is supported, and both ends received by plates or beams. A dead shore is an upright piece built up in a wall that has been cut or broken through for the purpose of making some alterations in the building.

SHOOTING. Planing the edge of a board straight, and out of winding.

SHOOTING BOARDS. Two boards joined together, with their sides lapped upon each other, so as to form a rebate for making short joints.

SHOULDER OF A TENON. The plane transverse to the length of a piece of timber from which the tenon projects. It should be at right angles to the length, though it does not always lie in the plane as here defined, but sometimes in different planes.

SHREAD HEAD

son.

The same as JERKIN HEAD, which see.

SHREDDINGS or FURRINGS. In old buildings, short slight pieces of timber fixed as bearers
below the roof, forming a straight line with the upper side of the rafters.
SHRINE. (Sax. Sepin.) A desk or cabinet; a case or box, particularly one in which sacred
things are deposited: hence applied to a reliquary and to the tomb of a canonised per-
The altar is sometimes called a shrine, and in this case its form and condition, and
the annexation of a statue to it, was of importance, because such tombs had greater
privileges than plainer monuments.
SHRINKING. The contraction of a piece of timber in its breadth by seasoning, hot
water, &c.
It is proportional to its breadth, the length not changing. Hence in un-
seasoned timber mitred together, such as the architraves of doors and windows, the
mitres are always close on the outside and open to the door, forming a wedge-like
hollow on each side of the frame. It is to avoid the effects of shrinking that narrow
boards called battens are used in floors.

SHUTE. See ARCHITECTS, list of, 243.
SHUTTERS. The boards which shut up the aperture of a window. See BOXINGS OF A
WINDOW.

SIDE POSTS. the truss.

Truss posts placed in pairs, disposed at the same distance from the middle of Their use is not only to support the principal rafters, &c., but to suspend the tie beam below. In extended roofs two or three pair of side posts are used. SIDE TIMBERS or SIDE WAVERS. The same as purlins, the first term being used in Somersetshire and the last in Lincolnshire.

SIMILAR FIGURES. Those whose several angles are respectively equal, and the sides about the equal angles proportional.

SIMONETTI. See ARCHITECTS, list of, 296.

SINE. A right line drawn from one end of an arch perpendicular upon the diameter, or it is half the chord of twice the arch. The sine of the complement of an arch is the sine

of what the arch wants of ninety degrees. The versed sine is that part of the diameter comprehended between the arc and the sine.

SINGLE FRAME and NAKED FLOOR. One with only one tier of joists.

SINGLE HUNG. An arrangement in a pair of window sashes, in which one only is movable.

SINGLE JOISTS FLOOR. One without binding joists.

SINGLE MEASURE. A term applied to a door that is square on both sides.

Double mea

sure is when the door is moulded on both sides. When doors are moulded on one side and are square on the other, they are accounted measure and half.

SISSIVERNE.. See ARCHITECTS, list of, 101.

SITE. (Lat. Situs.) The situation of a building; the plot of ground on which it stands. SKEW BACK. In a straight or curved arch, that part of it which recedes on the springing from the vertical line of the opening.

SKIRTING or SKIRTING BOARD. The narrow board placed round the margin of a floor, which, where there is a dado, forms a plinth for its base; otherwise, it is a plinth for the

room itself. Skirting is either scribed close to the floor or let into it by a groove; in the former case a fillet is put at the back of the skirting to keep it firm.

SKIRTS. Several superficies in a plane, which would cover a body when turned up or down without overlapping.

SKREEN. See SCREEN.

SKYLIGHT. A frame consisting of one or more inclined planes of glass, placed in a roof to light passages or rooms below.

SLAB. An outside plank or board sawed from the sides of a timber tree, and frequently of very unequal thickness. The word is also used to express a thin piece of marble,

consisting of right angles and plane surfaces.

SLATE. See Book II. Chap. II. Sect. 8.

See CHIMNEY.

SLATERS' WORK. See Book III. Chap. II. Sect. 6.

SLEEPERS. Horizontal timbers disposed in a building next to the ground transversely under walls, ground joists, or the boarding of a floor. When used on piles they are laid upon them, and planked over to support the superincumbent walls. Underground joists either lie upon the solid earth, or are supported at various parts by prop stones. When in the former position, having no rows of timber below, these ground joists are themselves called sleepers. Old writers on practical architecture call those rafters lying in the valley of a roof, sleepers; but in this sense the word is now obsolete. SLIDING RULE. One constructed with logarithmic lines, so that by means of another scale sliding on it, various arithmetical operations are performed merely by inspection. SLIT DEAL. See BOARD.

SLUICE. A stop against water for the drainage or supply with water of a place. It is hung with hinges from the top edge when used merely as a stop against the water of a river; but when made for supply as well, it moves vertically in the groove of its frame by means of a winch, and is then called a penstock.

SMITHERY and IRONMONGERY. See Book II. Chap. III. Sect. 10.

SMOOTHING PLANE. See p. 364.

SNACKET. A provincial term for the hasp of a casement.

SNIPE'S BILL PLANE. One with a sharp arris for getting out the quirks of mouldings. SOANE. See ARCHITECTS, list of, 316.

SOCKET CHISEL. A strong tool used by carpenters for mortising, and worked with a mallet. SOCLE OF ZOCLE. A square member of less height than its horizontal dimension, serving to raise pedestals or to support vases or other ornaments. The socle is sometimes continued round a building, and is then called a continued socle. It has neither base nor

cornice.

SOFFITA, SOFFIT, or SOFITE. (Ital.) A ceiling; the lower surface of a vault or arch.

A

term denoting the under horizontal face of the architrave between columns; the under surface of the corona of a cornice.

SOILS. A provincial term, chiefly, however, used in the north, signifying the principal

rafters of a roof.

SOLDER. A metallic composition used in joining together or soldering metals. SOLID. (Lat.) In geometry, a body which has length, breadth, and thickness; that is, it is terminated or contained under one or more plane surfaces, as a surface is under one or more lines. Regular solids are such as are terminated by equal and similar planes, so that the apex of their solid angles may be inscribed in a sphere.

SOLID ANGLES. An angle formed by three or more angles in a point, and whereof the sum of all the plane angles is less than three hundred and sixty degrees, otherwise they would constitute the plane of a circle and not of a solid.

SOLID SHOOT. See WATER SHOOT.

SOLIVE. The French term for a joist,

which builders lay their ceilings.

SOMMERING. See SUMMERING.

rafter, or piece of wood, either slit or sawed, with The term is rarely used in the English language.

SORTANT ANGLE. The same as SALIENT ANGLE, which see.

SOSTRATUS. See ARCHITECTS, list of, 25.

SOUFFLOT. See ARCHITECTS, list of, 299.

SOUND-BOARD.
speaker.
SOUND-BOARDING.

The same as a canopy or type over a pulpit, to reverberate the voice of the

In floors, consists of short boards placed transversely between the joists, and supported by fillets fixed to the sides of the latter for holding pugging, which is any substance that will prevent the transmission of sound from one story to another. The narrower the sound-boards the better. The fillets on which they rest may be about three-quarters of an inch thick and about an inch wide, nailed to the joists at intervals of a foot. See BOARDING FOR PUGGING.

SOUSE (Fr.) or SOURCE. A support or under-prop.

SPAN. An imaginary line across the opening of an arch or roof, by which its extent is

SPAN ROOF.

One consisting of two inclined sides, in contradistinction to shed or leanto roofing. It may be with simple rafters, with or without a collar beam, or when of increased span may be trussed, the term only applying to the external part. SPANDREL. The irregular triangular space between the outer curve or extrados of an arch,

a horizontal line from its apex, and a perpendicular line from its springing.

SPANDREL BRACKETING. A cradling of brackets fixed between one or more curves, each in a vertical plane, and in the circumference of a circle whose plane is horizontal.

SPANISH ARCHITECTURE. See Book I. Chap. II. Sect. 19.

SPAR-PIECE. A name given in some places to the collar beam of a roof.

SPARS. The common rafters of a roof for the support of the tiling or slating. SPECIFICATION. A description at length of the materials and workmanship to be used and employed in the erection of any building. See Book II. Chap. III. Sect. 13. SPECIFIC GRAVITY. A gravity or weight of every solid or fluid compared with the weight of the same magnitude of rain water, which is chosen as the standard of comparison, on account of its being subject to less variation in different circumstances of time, place, &c., than any other solid or fluid. By a fortunate coincidence, at least to the English philosopher, it happens that a cubic foot of rain water weighs 1000 ounces avoirdupois; consequently, assuming this as the specific gravity of rain water, and comparing all other bodies with this, the same numbers that express the specific gravity of bodies will at the same time express the weight of a cubic foot of each in avoirdupois ounces, which affords great facility to numerical computations. Hence are readily deduced the following laws

of the specific gravity of bodies : —

1. In bodies of equal magnitudes the specific gravities are directly as the weights or as their densities. 2. In bodies of the same specific gravities the weights will be as the magnitudes. 3. In bodies of equal weights the specific gravities are inversely as the magnitudes. 4. The weights of different bodies are to each other in the compound ratio of their magnitudes and specific gravities.

Thus it is obvious, that if of the magnitude, weight, and specific gravity of a body any two be given, the third may be found; and we may thus arrive at the magnitude of bodies which are too irregular to admit of the common rules of mensuration; or, by knowing the specific gravity and magnitude, we may find the weight of bodies which are too ponderous to be submitted to the action of the balance or steel yard; or, lastly, the magnitude and weight being given, we may ascertain their specific gravities.

TABLE OF SPECIFIC GRAVITIES

(Extracted from Davies, Lavoisier, Young, and other authentic sources).
Note. - Water at 60° is assumed 1000 specific gravity.

SPECUS. (Lat.) In ancient architecture, the canal into which the water flowed in aqueducts raised above the surface of the ground, and constructed of hewn stones or bricks. It was covered with a vault to preserve the water from the sun, and from being mixed with rain water. The specus was sometimes covered with flat stones, laid horizontally, as in the Aqua Martia, part of the Aqua Claudia, and the aqueduct of Segovia. Sometimes the same arcade carried several of these canals one above the other.

SPHÆRISTERIUM. A building for the exercise of the ball; a tennis court. The ancients
generally placed sphæristeria among the apartments of their baths and gymnasia. They
were also placed in large villas, as in those of Pliny the younger.
SPHERE. (Gr. Zpaipa.) A solid, whose surface is at every point equally distant from a
certain point within the solid, which point is called the centre of the sphere. Every
sphere is equal to two-thirds of its circumscribing cylinder, that is, it is equal to a
cylinder whose ends are circles, equal to a great circle of the sphere, and whose height is
equal to the diameter of the same.

SPHERICAL BRACKETING. That so formed that the surface of the plastering which it is to
receive forms a spherical surface.
SPHEROID. See CONOID.
SPHEROIDAL BRACKETING.

SPINA. See CIRCUS.
SPINTHARUS.

That formed to receive the plastering of a spheroid.

See ARCHITECTS, list of, 9.

SPIRAL. A curve which makes one or more revolutions round a fixed point, and does not return to itself.

SPIRE. (Gr. Zaupa, a twisting.) In ancient architecture, the base of a column, and sometimes the astragal or torus; but among the moderns it designates a steeple diminishing as it ascends, either pyramidally or conically.

SPLAYED. A term applied to whatever has one side making an oblique angle with the other; thus, the heading joists of a boarded floor are frequently splayed in their thickness; as are also the jambs or sides of a window. In the latter case, the practice is for the better lighting of a room. The word fluing is sometimes applied to an aperture, in the same sense as splayed.

SPRING BEVEL OF A RAIL.

The angle made by the top of the plank, with a vertical plane touching the ends of the railpiece, which terminates the concave side. SPRINGED. In boarding a roof, the setting the boards together with bevel joints, for the purpose of keeping out the rain.

SPRINGER. The impost or place where the vertical support to an arch terminates, and the curve of the arch begins; the term is sometimes used for the rib of a groined roof. SPRINGING COURSE. The horizontal course of stones, from which an arch springs or rises; or that row of stones upon which the first arch stones are laid.

SQUARE. (Lat. Quadra.) A figure of four equal sides, and as many equal angles; also, an area of such form surrounded by houses, and ornamented in the centre with a lawn, shrubs, trees, &c. In joinery, a work is said to be square framed, or framed square, when the framing has all the angles of its styles, rails, and mountings square without being moulded. The word is also applied to an instrument for setting out angles square. See CARPENTER'S SQUARE.

SQUARE SHOOT. A wooden trough for discharging water from a building.

SQUARE STAFF. A piece of wood placed at the external angle of a projection in a room to secure the angle, which if of plaster would be liable to be broken, and at the same time to allow a good finish for the papering.

SQUARING A HANDRAIL. The method of cutting a plank to the form of a rail for a staircase, so that all the vertical sections may be right angles.

SQUARING A PIECE OF STUFF. The act of trying it by the square, to make the angles right angles. STABLE. (Lat.) A building for the accommodation of horses.

STACK OF CHIMNEYS. See CHIMNEY.

The

STADIUM. (Gr.) In ancient architecture, an open space wherein the athleti or wrestlers exercised running, and in which they contested the prizes. It signifies also the place itself where the public games were celebrated, often formed a part of the gymnasia. word also denotes a measure of length among the Grecians, of 125 paces. STAFF-BEAD. See ANGLE-BEAD.

STAGE. A floor or story. In a theatre, the floor on which the performers act. The stage of a buttress is, in ecclesiastical architecture, the part between one splayed projection and the next.

STAIR. (Sax. Stægen, to step.) A stone, or piece of other material, by which a person raises himself one step. A series of steps or stairs for ascending from the lower to the upper part of a building, when enclosed by a wall, is called a staircase.

STAIRCASE.

That part or subdivision in a building containing the stairs, which enable persons to ascend or descend from one floor to another. See Book III. Chap. I. Sect. 23. for its construction.