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WALL-PLATE, a piece of timber placed in or upon awall to receive the ends of joists or rafters.

WALLS, (perhaps from the Latin vallum, a fence,) thosemasses of materials which generally have their faces in ver-tical or plumb-lines ; or, at least are so disposed, that aplumb-line from any point in either surface will fall entirelywithin the surface, or within the thickness of the wall.

In walls constructed for shelter, if the materials cannot bejoined without interstices, those interstices ought to be soclosed as to render the work impervious to rain or drift.

The materials with which walls are generally constructedare brick or stone. Stone walls may be built either of roughor squared stones. When the exterior walls of dwelling-houses are to be constructed of rough stone, the stones oughtto be laid in mortar ; but when they are squared andsmoothed, this is not necessary. The ancients, in buildingtheir edifices with squared stones, seldom laid them inmortar; but their joints and beds were so exactly wrought,as to come nearly in contact with each other. See StoneWalls.

As bricks cannot be Iformed so regularly as stones, onaccount of the burning, they are usually laid in mortar. SeeBricklaying and Brickwork .

From the definition given of a wall, founded upon theaxiom, that every material which overhangs has a tendencyto fall, or to break off, or to overturn the structure of which itis a part, it is evident, that as a wall rises it ought either todiminish in its thickness, or to follow the plumb-line.

Walls common to two apartments are called partition walls,or simply partitions. When a wall is divided or separatedby ornaments, apertures, or projections, it is said to be inter-mitted; but if uninterrupted, it is called a continued wall.It is, however, generally understood, that when a wall hasapertures without projections, as columns and pilasters, it issai l to be continued, which is contradictory to the commonacceptation of the term.

Walls, Abutments in, the beds that are prepared for thespringing of an arch.

Walls, Cased, those that are faced up anew all round thebuilding, in order to cover an inferior material, or old workgone to decay.

Walls, Empleclon, those which are built in regtdarcourses, with the stones smoothed in the face of the work :they are of two kinds, Roman or Grecian. The difference is,that the core of the Roman emplecton is rubble ; whereas inthe Grecian it is built in the same manner as the face, andevery alternate stone goes through the entire thickness of thewall.

Walls, Isodomum, those where the courses are of equalthickness, compact, and regularly built; but the stones arenot smoothed on the face.

Walls, Pseudo - isodomum, those which have unequalcourses.

For other particulars respecting walls, see the articlesabove referred to ; also Building, Rise, and Mensuration.

WATER-CLOSET, an apartment so generally known asto render any definition of it unnecessary. There are nogood houses without one or more of them. Their construc-tion belongs entirely to the engineer : the chief thing whichthe architect has to attend to is, to place his water-closets insuch a situation as to be isolated from the principal apart-ments, to conceal them from general observation, and tomake them as accessible as possible. The number of Water-closets in a house ought to be in proportion to the magnitudeof the building ; in large mansions, a certain number ofwater-closets must be appropriated to the servants, as wellas to the family itself. One of the principal things which

the architect must attend to is, to prevent all recoil or reti> rof noxious effluvia.

Water Shoot, a wooden trough for discharging ra ' nwater from a building.

Water Table, the upper surface of a coping, or pi' ( 'J ( j < ’tion, where the superior part of a wall recedes from tinferior or lower part. . ,

Water tables are frequently used in edifices of the pomstyle, particularly near tiie base of the building; as in otresses consisting of several stages, where the sloping P al ’which cover the solids below, are called water-tables.

WAY-WISER. See Perambulator. e

WEATHER BOARDING, signifies the nailingboards lapped upon each other, so as to prevent rain or O'from passing through. For this purpose, the boards al ^generally made thinner on one edge than on the other ; l ,aIticularly when the work is intended to be permanent :boards thus formed are called feather-edged boards.using feather-edged boards, the thick edge of the uppboard is laid upon the thin edge of the board below, al)an inch over, or, in very secure work, an inch and a b a ’the nails being driven through the lap.

WEATHERING, a slight inclination given to copmg s 0ledges of walls, for the purpose of throwing off the rain.

WEATHER MOULDING, a moulding carried over^door or window, for the purpose of diverting rain-water Dthe parts beneath ; otherwise termed drip-stone, or label.

Weather Tiling, the covering of an upright or wall Wttiles. . .

WEDGE, (from the Danish wegge .) Writers on mechanj^’in treating of the wedge, have frequently drawn false consions respecting the proportion which exists between ^impelling power applied to the head, and the resisting P 0 ",. jopposed to the sides; and those conclusions have r eaU . ^from false opinions concerning the directions of the resi °powers. , tb y

It is evident, that when wood or other substance is S P*' ^a wedge which does not fill the cleft, that is, when theof the cleft is more acute than that of the wedge, the P ^or action of each side of the wedge, equal and opposite toresistance of the cleft, must be resolved into two ; the 01 ^

the direction of the side of the cleft, which tends to . U j 0ll)forward ; and the other perpendicular to that dnwhich tends to tear it asunder. It is by not attending 1 oabove solution, that writers on this subject have been ^mistakes ; for, instead of considering the powers win erin those two directions, they have imagined a single P ^only as acting obliquely on each side. But if the s' -j e rthe wedge are perfectly polished, as we must here c _ e jthem, no single permanent power can be applied t0 theany one of them, unless its direction be perpendicutaplane of the side to which it is applied ; thereloi >oblique powers, applied on opposite sides of the san ^,jj 0 n ofare at least necessary to sustain each other and the ac t j one d,the plane; and in the case of the wedge above nien 3 bethe directions of those two oblique powers will a the

perpendicular to each other, as will appear obvious

two following Propositions. . j ggctio 11

Proposition I. Figure 1.—Let a b c be a vertica ^ j i( , a dpassing through the centre and at right angles to ^ th> 9and sides of any isosceles wedge ; also in the P la ”j cA , \A

section, and at right angles to its sides, A b, b c, -three powers be applied, such, that their direc11 0I1S gta £n th emutually intersect in the axis, and their efforts su ^ #n dwedge in equilibrio; which three powers are as A B >

CA , respectively. v oVf etS ’

Let l m, k i, e d be the directions of these thiee F