to be removed, and at the same time are pushed forward by levers applied behind. When blocks of marble, or other very heavy weights, are to be moved, they use what are called endless rolls. These, to give them the greater force and prevent their bursting, are made of wood joined together by cross-quarters, double the length and thickness of the common rollers, and girt with iron hoops at each end. At a foot from the ends are two mortises pierced through and through, into which are put the ends of long levers, which the workmen draw by ropes fastened to the ends, still changing the mortise as the roll has made a quarter of a turn.

ROMAN ARCHITECTURE. See Book I. Chap. II. Sect. 13.

ROMAN ORDER. The same as COMPOSITE ORDER, which see.

ROMUALDUS. See ARCHITECTS, list of, 71.

ROOD. (Sax. Rode.) A cross, crucifix, or figure of Christ on the cross placed in a church. The holy rood was one, generally as large as life, elevated at the junction of the nave and choir, and facing to the western entrance of the church. The rood loft was the gallery in which the rood and its appendages were placed. This loft, or gallery, was commonly placed over the chancel screen in parish churches. In Protestant churches the organ now occupies the original place of the rood loft. The rood tower or steeple was that

which stood over the intersection of the nave with the transepts. ROOF. (Sax. Ror, Hnor.) The exterior covering of a building, for whose principles of construction and various sorts the reader is referred to p. 544, et seq.

ROOFING. The assemblage of timbers, and covering of a roof whose pitch in this climate, for different coverings, is shown in the following table:

:

Inclination to the Horizon.

3° 50"

22

26

33

29 41

29 41

Pan tiles

Thatch

two-sevenths.

two-sevenths.

two-ninths.

one-half.

ROOM. (Sax. Rum.) An interior space or division of a house, separated from the remainder of it by walls or partitions, and entered by a doorway.

ROOMS, PROPORTIONS OF. See Book III. Chap. I. Sect. 25.

ROSE or ROSETTE. An ornament of frequent use in architectural decorations. The centre of the face of the abacus in the Corinthian capital is decorated with what is called

a rose.

ROSE WINDOW.

A circular window with compartments of mullions and tracery branching from a centre, sometimes called a catharine wheel or marigold window. ROSTRUM. (Lat.) Literally, the beak of a bird; also the beak or fore-part of a ship; the elevated platform in the Forum of ancient Rome, whence the orators addressed the people, so called from its basement being decorated with the prows of ships. The term is now used generally to signify a platform or elevated spot from which a speaker addresses his audience.

ROT, DRY. An extremely destructive disease incident to timber. See p. 490.

ROTUNDA OF ROTONDO. (Ital.) A building circular on the interior and exterior, such as the Pantheon at Rome. See CIRCULAR BUILDINGS.

ROUGH-CAST. A species of plastering used on external walls, consisting of a mixture of lime, small shells or pebbles, occasionally fragments of glass and similar materials. This is usually applied to cottages.

RUDENTURE. (Lat. Rudis, a rope.) The same as CABLING, which see.

RUDERATION. (Lat. Ruderatio.) A method of laying pavements, mentioned by Vitruvius, and according to some, of building walls with rough pebbles and mortar. called statumen by Vitruvius was made of lime and sand.

Ruiz.

See ARCHITECTS, list of, 226.

The mortar

RULE. An instrument for measuring short lengths. Of rules there are various sorts, each adapted to the class of artificers for whose use they are made. Thus, there are stonecutters' rules, masons' rules, carpenters' rules, sliding and parallel rules, &c. The sliding rule is, however, of more general use, as it solves a number of questions from the change of the position of the slider by inspection, and therefore of much importance to the less educated artisan.

RURAL ARCHITECTURE. See Book III. Chap. III. Sections 22, 23, and 24.
RUSSIAN ARCHITECTURE. Book I. Chap. II. Sect. 20.

RUSTIC ORDER. A species of building wherein the faces of the stones are hatched or picked with the point of a hammer.

RUSTIC QUOINS or COINS. The lapides minantes of Vitruvius, the stones placed on the

external angles of a building projecting beyond the naked of the wall. The edges are bevelled, or the margins recessed in a plane parallel to the face or plane of the wall. RUSTIC WORK. A mode of building masonry wherein the faces of the stones are left rough, the sides only being wrought smooth where the union of the stones takes place. It was a method much practised at an early period, and re-introduced by Brunelleschi at the revival of the arts. The most common sorts of rustic work are the frosted, which has the margins of the stones reduced to a plane parallel to that of the wall, the intermediate parts having an irregular surface; vermiculated rustic work, wherein the intermediate parts present the appearance of having been worm-eaten; chamfered rustic work, in which the face of the stones being smoothed and made parallel to the surface of the wall, and the angles bevelled to an angle of one hundred and thirty-five degrees, with the face of the stone, where they are set in the wall, the bevel of the two adjacent stones forms an internal right angle.

S.

SABLIERE. (Fr.) An obsolete word, signifying a piece of timber as long as a beam, but not so thick.

SACCHETTI. See ARCHITECTS, list of, 286.

SACELLUM. (Lat.) In ancient Roman architecture, a small inclosed space without a roof. Small sacella, too, were used among the Egyptians, attached frequently to the larger temples. In old church architecture, the term signifies a monumental chapel within a church, also a small chapel in a village.

SACOME. (Ital.) The exact profile of a member or moulding, applied by the French to the mouldings themselves.

SACRARIUM. (Lat.) A small sacred apartment in a Roman house, devoted to a particular deity; also the cella, penetrale or adytum of a temple.

SACRISTY. See DIACONICUM.

SADDLE-BACKED COPING. See COPING.

SAG or SAGGING. The bending of a body by its own weight when resting inclined or horizontally on its ends.

SAGITTA. (Lat. an arrow.) A name sometimes applied to the keystone of an arch. In geometry, it is often employed to signify the abscissa of a curve; and in trigonometry it is the versed sine of an arc, which, as it were, stands like a dart upon the chord. SAIL OVER. See PROJECTure.

SALIANT. (Fr.) A term used in respect of a projection of any part or member. SALLY. A projecture. The end of a piece of timber cut with an interior angle formed by two planes across the fibres. Thus the feet of common rafters, and the inclined pieces which support the flying steps of a wooden stair, are frequently cut; as are, likewise, the lower ends of all inclined timbers which rest upon plates or beams. SALON OF SALOON. (Fr.) A lofty and spacious apartment, frequently vaulted at top, and usually comprehending the height of two floors with two tiers of windows. Its place is commonly in the middle of a building, or at the head of a gallery, &c. In palaces it is the state room.

SAN GALLO ANTONIO.

See ARCHITECTS, list of, 199.

SAN GALLO DI GIUL. See ARCHITECTS, list of, 178.

SAN LUCANO. See ARCHITECTS, list of, 183.
SAN MICHeli. See ARCHITECTS, list of, 213.
SAND. See Book II. Chap. II. Sect. 10.

SANDSTONE. In mineralogy, a stone principally composed of grains, or particles of sand, either united with other mineral substances or adhering without any visible cement. The grains or particles of sandstone are generally quartz, sometimes intermixed with feldspar or particles of slate. When lime is the cementing matter the stone is called calcareous sandstone. The cementing matter is not unfrequently oxide of iron intermixed with alumine. The particles of sand in these stones are of various sizes, some being so small as to be scarcely visible. See Book II. Chap. II. Sect. 1. SAP.

The juice or pith of trees that rises from the earth and ascends into the arms, branches, and leaves, to feed and nourish them. Also that part of the stem or wood of the body of a tree that is soft, white, &c. The term is used also as a verb, to denote the undermining a wall by digging a trench under it.

SAPHETA. The same as SOFFITE or SOFITE, which see.

SARACENIC ARCHITECTURE. See Book I. Chap. II. Sect 10.

SARCOPHAGUS. (Zapέ flesh, and Hayw, to eat.) A tomb or coffin made of one stone. From Pliny it appears to have been originally applied as the name of a stone found in the Troad, which, from its powerful caustic qualities, was selected for the construction of tombs. From its frequent application to this purpose the name became at length used for the tomb itself. Sarcophagi were made of stone, marble, alabaster, porphyry, &c. The Greeks sometimes made them of hard wood, as oak, cedar, or cypress, which resisted

moisture; sometimes of terra cotta, square, the angle being rounded.

and even of metal. The form was usually a long The lid varied both in shape and ornament. Those of the primitive Christians often enclosed several corpses, and were ornamented with several sets of bassi rilievi. Those of higher antiquity were frequently sculptured with great taste and beauty of design, the figures being those of the deceased, or parties connected with them, allegorical or mythological. The Egyptian sarcophagi are sculptured with hieroglyphics. Those of the Greeks and Romans sometimes represent Sleep and Death with their legs crossed, one hand supporting the head and the other holding an inverted torch; sometimes Mercury is represented conducting the Souls and Charon ferrying them over in his bark. Occasionally we find on them groups of bacchanals and bacchic scenes.

SASH. (Fr. Chasis, a frame.) A frame for holding the glass of windows, and so formea as to be raised and depressed by means of pulleys. Sashes are single or double hung, or hung with hinges. See p. 572.

SASH FRAME. The frame in which the sashes are fitted for the convenience of sliding up and down, or, when hung with hinges, to receive them after the manner of hanging a door. SAURUS. See ARCHITECTS, list of, 34.

SAW. (Dutch, SAwe.) A tool made of a thin plate of steel, formed on the edge into regular teeth for cutting wood, stone, &c. Saws are of various kinds. See p. 565. SAW-FIT. A pit excavated for sawing timber. The sawing is performed by two persons called sawyers, one standing above and the other below. Much of the labour, however, is saved by the use of a saw-mill, or machine moving a circular saw, which by its revolutions and keeping the timber close up, performs the work quicker and better than can be done by the labour just described.

SAXON ARCHITECTURE. See Book I. Chap. III. Sects. 1 and 2.

SAXULPHUS. See ARCHITECTS, list of, 66.

SCABELLUM. (Lat.) A species of pedestal anciently used to support busts or statues. It was high in proportion to its breadth, ending in a kind of sheath, or in the manner of a baluster.

SCAFFOLD. (Fr. Echaufaud.) An assemblage of planks or boards sustained by pieces of wood made fast to vertical poles, and at the other end often resting on the walls, by means whereof the workmen carry up a building, or plasterers complete their work in the interior of houses. On the Continent, scaffolds for public building are much more solidly constructed than in this country.

SCAGLIOLA. (Ital.) A species of plaster or stucco invented at Carpi, in the state of Modena, by Guido Sassi, between 1600 and 1649. It is sometimes called mischia, from the mixture of colours introduced in it. It was not, however, till the middle of the eighteenth century that the art of making scagliola was brought to perfection. The following is the method of making columns and pilasters:-A wooden cradle, composed of thin strips of deal or other wood is made to represent the column designed, but about 2 inches less in diameter than the shaft is intended to be when finished. This cradle is lathed round, as for common plastering, and then covered with a pricking-up coat of lime and hair. When this is quite dry, the scagliola artist commences his operations, and, by imitating the rarest and most precious marbles, produces a work which cannot be, except by fracture or sound, discovered to be counterfeit. The purest gypsum which can be obtained is broken into small pieces, and calcined. As soon as the largest fragments lose their brilliancy, the fire is withdrawn; the calcined powder is passed through a very fine sieve, and mixed up with a solution of Flanders glue, isinglass, &c. In this solution the colours are diffused that are required to be imitated in the marble; but if the work is to be of various colours, each colour is separately prepared, and they are afterwards mingled and combined nearly in the same manner that a painter mixes the primitive colours on his palette to compose his different tints. When the powdered gypsum is prepared and mingled for the work, it is laid on the shaft of the column or other surface over the pricked-up coat of lime and hair, and it is then floated with proper moulds of wood, the artist during the floating using the colours necessary for the imitation, by which means they become mingled and incorporated with the surface. The process of polishing follows; and this is done by rubbing the surface with pumice-stone in one of his hands, while with the other he cleans it with a wet stone. It is then polished with tripoli and charcoal and fine and soft linen; and after going over it with a piece of felt dipped in a mixture of oil and tripoli, he finishes with application of pure oil. SCALE. (Sax.) A line divided into a certain number of equal parts, usually on wood, ivory, or metal, for laying down heights and distances in mathematical and architectural drawing. There are various sorts of scales; as, the plane scale, Gunter's scale, the diagonal scale, &c.; but the most generally useful scale is that wherein the objects are drawn some aliquot part of their real size, as a tenth, twelfth, twentieth, twenty-fourth, &c. SCALENE TRIANGLE. (Σkaλŋvos, oblique.) In geometry, one whose sides are all unequal. SCAMILLI IMPARES. A term used by Vitruvius, which has puzzled all the commentators.

It probably signifies certain blocks which serve to raise some of the members of a building, which, from being placed below the level, or below the projection of certain ornaments, might be lost to the eye.

SCAMILLUS. A small plinth below the bases of the Ionic and Corinthian columns.

SCAMMOZZI. See ARCHITECTS, list of, 247.

SCANDULE. (Lat.) In early buildings of the Romans, shingles or flat pieces of wood used for covering instead of tiles. According to Cornelius Nepos, this was the only covering used in Rome till the war with Pyrrhus in the 470th year of the city. SCANTLING. (Fr.) The dimensions of a piece of timber in breadth and thickness.

It is

also a term used to denote a piece of timber, as of quartering in a partition, when under five inches square, or the rafter, purlin, or pole plate of a roof. In masonry, scantling is the length, breadth, and thickness of a stone.

SCAPE OF SCAPUs. (Gr.) The shaft of a column; also the little hollow, above or below, which connects the shaft with the base, or with the fillet under the astragal.

SCAPLING. A method of tooling the face of a stone.

SCARFING. The joining of two pieces of timber by bolting or nailing transversely together, so that the two appear but one. See p. 538.

SCENE. (Gr. Zknn.) Strictly an alley or rural portico for shade or shelter, wherein, according to Cassiodorus, theatrical pieces were first represented. When first applied to a theatre, it signified the wall forming the back of the stage, but afterwards came to mean the whole stage, and is now restricted to the representation of the place in which the drama represents the action. According to Vitruvius, the Greek scene was occupied in the middle by a great door, called the royal door, because decorated as the gate of a palace. At the sides were smaller doors, called hospitalia, because representing the entrances to habitations destined for strangers, which the Greeks commonly placed on the two sides of their houses.

SCENOGRAPHY. (Gr.) The method of representing solids in perspective.

SCHEME OF SKENE ARCH. One which is a segment of a circle.

SCHENE. (Gr.) The representation of any design or geometrical figure by lines so as to make it comprehensible.

SCHOLIUM. In mathematics, a remark after the demonstration of a proposition, showing how it may be done some other way, or giving some advice or precaution to prevent mistakes, or adding some particular use or application thereof.

SCIAGRAPHY OF SCIOGRAPHY. (Gr. Ekiα, a shadow, and гpapw, I describe.) The doctrine of projecting shadows as they fall in nature. See Book II. Chap. IV. Sect. 3. SCOPAS. See ARCHITECTS, list of, 16.

SCOTIA. (Gr. EKOTIα, darkness.) The hollow moulding in the base of a column between the fillets of the tori. It receives the name from being so much in shadow. The scotia was, from its resemblance to a pulley, called also Tрoxinov. It is most frequently formed by the junction of circular areas of different radii, but it ought rather to be profiled as a portion of an ellipsis.

SCRATCH WORK. (It. Sgraffiata.) A species of fresco with a black ground on which a white plaster is laid, which being scratched off with an iron bodkin, the black appears through the holes, and serves for shadows.

SCREEN. (Lat. Excerno.) An instrument used in making mortar, consisting of three wooden ledges joined to a rectangular frame at the bottom, the upper part of which frame is filled with wirework for sifting the sand or lime. This term is used in ecclesiastical architecture to denote a partition of wood, stone, or metal, usually so placed in a church as to shut out an aisle from the choir, a private chapel from a transept, the nave from the choir, the high altar from the east end of the building, or an altar tomb from one of the public passages or large areas of the church. In the form and ornamental detail of screens, the ancient artists appear to have almost exhausted fancy, ingenuity, and taste.

SCREW. (Dutch, Scroeve.) One of the six mechanical powers, chiefly used in pressing or squeezing bodies close, though sometimes also in raising weights. See Book II. Chap. I. Sect. 8.

SCRIBING. Fitting the edge of a board to a surface not accurately plane, as the skirting of a room to a floor. In joinery, it is the fitting one piece to another, so that the fibres of them may be perpendicular to each other, the two edges being cut to an angle to join.

SCROLL. A convolved or spiral ornament variously introduced.

Also the volutes of the Ionic and Corinthian capital. See fig.

1046.

Fig. 1046.

SCULLERY. The apartment for washing up the dishes and utensils wherein the scullion works. SCULPTURE. (Lat. Sculpo, to carve.) The art of imitating forms by chiselling and working away solid substances. It is also used to denote the carved work itself. Properly, the word includes works in clay, wax, wood, metal, and stone; but it is generally re

stricted to those of the last material, the terms modelling, casting, and carving being applied to the others.

SEALING.

The fixing a piece of wood or iron on a wall with plaster, mortar, cement, lead, or other binding, for staples, hinges, joints, &c.

SEASONING TIMBER. See p. 491.

SECANT. (Lat.) A line that cuts another. In trigonometry, the secant is a line drawn to the centre from some point in the tangent, which consequently cuts the circle. SECOS. See ADYTUM.

SECTION OF A BUILDING. A geometrical representation of it as divided or separated into two parts by a vertical plane, to show and explain the construction of the interior. The section not only includes the parts that are separated, but also the elevation of the receding parts, and ought to be so taken as to show the greatest number of parts, and those of the most difficult construction. Of every building at least two sections should be made at right angles to one another, and parallel to the sides. A section of the flues should also be made, in order to avoid placing timbers near them.

SECTION OF A SOLID. The plane of separation dividing one part from the other. It is understood to be always a plane surface.

SECTOR. An instrument for measuring or laying off angles, and dividing lines and circles into equal parts.

SECTOR OF A CIRCLE. The space comprehended between two radii and the arc terminated by them.

SEGMENT. (Lat.) A part cut off from anything. The area contained by the arc of a circle and a chord. In the segment of a circle the chord of the arc is called the base of the segment, and the height of the arc the height of the segment.

SEGMENT OF A SPHERE. A portion cut off by a plane in any part except the centre, so that the base of such segment must be always a circle, and its surface a part of the sphere. SELL. See CILL and APERTURE.

SEMICIRCLE. The half of a circle contained by the diameter and circumference.
SEMICIRCULAR ARCHES. Those whose arcs are semicircular.

SENNAMAR. See ARCHITECTS, list of, 55.

SEPULCHRE. (Lat. Sepelire, to bury.) A grave, tomb, or place of interment. The cenotaph was an empty sepulchre raised in honour of a person who had had no burial. SERAGLIO. The palace of an eastern prince, but more particularly that in which the females are lodged.

SERVANDONI. See ARCHITECTS, list of, 288.

SESSPOOL. See CESSPOOL.

SETT. In piling, a piece placed temporarily on the head of a pile which cannot be reached by the monkey or weight from some intervening matter.

SETTING. The hardening of cement. The term is also used in masonry for fixing stones in walls or vaults, in which the greatest care should be taken that the stones rest firmly on their beds, and that their faces be ranged in the proper surface of the work. SETTING-OUT ROD. One used by joiners for setting-out frames, as of windows, doors, &c. SETTLEMENTS. Those parts in which failures by sinking in a building have occurred. SETT-OFF. The projecting part between the upper and lower portion of a wall where it diminishes in thickness.

SEVERUS. See ARCHITECTS, list of, 43.

SEVERY. A compartment or division of scaffolding. It is also a separate portion or division of a building corresponding with the modern term compartment, being as it were severed or divided.

SEWER. A drain or conduit for carrying off soil or water from any place. See Book II. Chap. III. Sect. I.

SEXAGESIMAL. The division of a line, first into sixty parts, then each of these again into sixty, and so on, as long as division can be made. It is principally used in dividing the

circumference of a circle.

SHADOWS and SHADOWING. In drawing, the art of correctly casting the shades of objects and representing their degrees of shade. See Book II. Chap. IV. Sect. 3.

SHAFT. (Sax. Sceart.) The cylindrical part, or rather body, of a column, between the base and th capital. It is, properly, the frustum of a conoid, and is also called the fust, trunk, or body of the column.

SHAFT OF A CHIMNEY.

See CHIMNEY.

SHAFT OF A KING POST. The part between the joggles.

SHAKE. A fissure or rent in timber by its being dried too suddenly, or exposed to too great heat. Any timber when naturally full of slits or clefts is said to be shaky. SHANKS. (Sax.) The space between two channels of the Doric triglyph, sometimes called the legs o the triglyph. The ancients called the shank femur.