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juice of figs, and sometimes with liquid pitch ; after applica-tion, it is washed over with linseed oil.

For this purpose, mortar made of terras, puzzolana, tile-dust, or cinders, is mixed and prepared in the same manneras common mortar : only that these ingredients are mixedwith lime instead of sand, in a due proportion, which is abouthalf and half. The lime should be made of shells, or marble ;and in works which are sometimes dry and sometimes wet,instead of terras, which is very dear, tile-dust or cinder-dustmay be used.

Mortar, for sun-dials on walls, or for tablets to write on,may be made of lime and sand, tempered with linseed oil;or, for want of that, with skimmed milk. This will growto the hardness of stone. For buildings, one part of washedsoap-ashes, mixed with another of lime and sand, make a verydurable mortar.

MORTAR MILL, a machine contrived by Mr. Supple,but since much improved by others, for the purpose of savinglabour, and more effectually mixing the ingredients inmaking mortar.

MORTISE, or Mortice, (from the French , mortoise, per-haps derived from mordeo, to bite, or pinch,) in carpentry andjoinery, an excavation recessed within the surface of a pieceof timber, to receive a projection called a tenon, left on theend of another piece, in order to fix the two together at agiven angle. The sides of the mortise are generally fourplanes at right angles to each other,, and to the surfacewhence the excavation is made. See Carpentry andJoinery.

MORTISE LOCK, a lock made to fit into a mortise cut inthe style and rail to receive it.

MORTUARY, a term sometimes used to signify a burial-place.

MOSAIC, or Mosaic-Work , (from mosaieum, a corrup-tion of musaicum , as that is of musivum, as it was calledamong the Romans : but Scaliger derives it from the Greek,petra, and imagines the name was given to this sort of work,as being very fine and ingenious ; and Nebricensis is of opi-nion it was so called, because ex itlis picturis ornabanlermusea ,) an assemblage of little pieces of glass, marble, shells,precious stones, woods, or the like, of various colours, cutsquare, and cemented on a ground of stucco, &c., imitatingthe natural colours and gradations of painting. In this sense,mosaic work includes marquetry, or inlaid work, veneering,&c. But, in its more proper and restrained sense, mosaic onlytakes in works of stone, metals, and glass ; those of woodbeing distinguished by the name of marquetry or inlaying.(See those words.)

Others distinguish differently between mosaic and marque-try. In that properly called mosaic, they say the severalstones are all of the same colour ; and the changes and dimi-nutions of colours and shades are made by applying differentstones, one on another, but.all of the same colour. Marque-try , on the contrary, consists of stones of different colours ;and by these the several colours, shades, gradations, &c., areexpressed.

Mosaic seems to have taken its origin from paving : thefine effect and use of pavements composed of pieces of marbleof different colours,—so well joined together, as that, whendried, they might be polished, and the whole make a verybeautiful and solid body, which, continually trodden upon,and washed with water, was not at all damaged,—-gave thepainter the hint, who soon carried the art to a much greaterperfection, so as to represent foliages, masques, and othergrotesque pieces, of various colours, on a ground of blackor white marble. But nature not producing variety of coloursenough for them in marbles, to paint all kinds of objects,

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they thought of counterfeiting them with glass and n*coloured. . t iif

This kind of work is supposed to have originated 1,1East, to have been brought from Phenicia to Greece *thence to Rome , where it was used more especially f° r P‘ t 0 t 'ments. These pavements consisted for the most p‘ l ^patterns forming borders round a central figure or device* ‘ ^sometimes a group or subject; others consisted s0 e . [. lC fepatterns worked out in two or three colours, usually ‘ 0 jwhite, and red. Of all places, however, the arta* ve f<Byzantium carried this art into most extensive practice, c -ing both walls, pavements, and ceilings with such deed 9 j,,mosaics became indeed a very common method of el ^,| ie yment in Christian churches, both in Asia and Italy - pform the most characteristic decoration of the Basilica -a style of art, as well as a manufacture, musive "’Oibe said to have arisen wholly in the era of Christianity -material of which the mediaeval mosaics are formed g pchiefly glass, distinguishes them completely from the s tlated pavements of the Romans. Perhaps the n j. t li6approach to the manufacture, is the rude inlaid work ,,t

columns and fountains in some of the Pompeii g a ,,, ..jgti'

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all events, their applications is entirely peculiaranity. The apex of the apse was usually reserve-- ^species of decoration, which still constitutes the pecuhai ;of the ancient Italian churches. The solemn.gigantic »and the mysterious imagery of the mosaics, dimly seen ^darkness of the sanctuary, produce an effect deniedelaborate specimens of art. In one most important

they are infinitely preferable to paintings, because,

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their position and their character, they never ^ eC ^, a te ' 9objects of adoration. Usually speaking, the main ’e g jdftthe Saviour in the act of judging the world ; on eitSt. Peter and St. Paul : other saints are added, u f ua o peS otreference to the peculiar locality. Portraits of P ^ tl' 6emperors connect the sacred imagery with the annUage. Although not governe'd by any definite system,is a uniform course in the adaptation of the ornam enMosaic work is also common in Arabian edifices* ^ o9i iirso indeed as to become a feature of the style.were principally of porcelain, and were used in the i <of the lower part of the walls, and also for paveinenMoorish Architecture. te>'' l,r3 °i

A kind of mosaic work was common on th fsome of the mediaeval churches of Italy , as the „s0Pisa , where the walls of the fa$ade are decorated w ^ lil^jof pattern in black and white colours, brilliant reds ‘ ^ t( .rabeing interspersed occasionally. Another instance o j^rk' 1 ;decoration in mosaic is to be seen in the fa§ade ot

Venice.

Pictures in mosaic, properly so termed, andcomparatively recent introduction, differ frombeing merely copies or fac-siiniles of paintings, apP r °‘

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the

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appearance as nearly to pictures as possible. ivli* ;

mosaic works dates only from the ‘ commencement T

seventeenth century. The tints are graduated off giu-dto darker shades by using an indefinite number of ^pieces of glass of various intensities of colour, so v p« r 'those pieces which are contiguous exhibit scarcely ■ceptible difference to the eye. In the more ancient ql) ,tethe tints are not blended one into the other, but t 1

distinct, the outlines being hard, and the joints gtessera plainly visible. In these examplesattempt at making pictures ; they are treate ^ventional manner, so that such features are toas characteristic proprieties rather than defects- ^ pjos 8 'Florentine work may also be added to the h s

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