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WINDLASS, or Windlace, a machine for raising■weights, in which a cope or chain is wound about a cylin-drical body, moved by several levers.
Also, a handle, by which anything is turned.
WINDOWS, (from the Danish, vindue, or the Welsh ! wynt dor, a passage for the wind,) those apertures in wallsi through which light is transmitted to the interior of! buildings.
j Windows are generally of a rectangular form, the sides,
; or jambs, being vertical, and the bottom and lintel horizontal.
| Semicircular windows have a very elegant effect, particularly| in circular buildings, as was generally the practice of the! Romans; but those that are finished witli segments, or semi-: ellipses, are not so beautiful ; and much less so are such asare constructed of entire circles or ellipses, for which, fewor no precedents are to be found in the buildings of theancients.
Windows must be proportioned in height and width to theprincipal rooms. The dressings of windows are the sill, andthe insisting architrave, surrounding the upper part, crownedby a cornice and frieze. The breadth of the architrave maybe one-sixth of that of the aperture ; the frieze the same ;the height of the cornice will depend upon the number ofmouldings.
Windows should be so placed with respect to the principalroom, or dining and drawing-rooms, as to be equally distantfrom each end of the apartment, and equidistantly distributedin the principal front, of one size, with their edges or sidesin the same vertical lines. This adjustment will frequentlybe attended with difficulties ; and to accommodate the prin-ciple, an alteration of the proportions, in a small degree, willsometimes be necessary. In houses of the middle class,where economy is an equal consideration with elegance orbeauty, the windows frequently reach as high as the cornice,or even so high as to cut the cornice, wholly, or in part ; amutilation that destroys the beauty of the finishing. In suchcases, it would be better to have more lofty stories or lowerwindows. In large edifices, where proportions are con-sidered, the spaces above the windows are more ample, andallow a more elegant finish, with a greater repose for the eye.Further particulars respecting windows will be found underApartment, Building, Casement, House, Joinery, Sasii-; frame, and Skylight. See also Tracery , and Gothicj Architecture, &c.
I Plate I. Figure 1.—A window finished in the usual man-ner. No. 1. The elevation. No. 2. The flank.
| Figure 2.—The elevation of a window, where, the thick -j ness of the wall not being sufficient to allow of boxings, the| shutters are hinged upon a hanging style,j Figure 3.—The section of the foregoing.
Figure 4.—Section and plan of the sash-frame and shuttersof a window, showing the same finishing, whether the shut-ters be folded in their boxings to admit light, or extended to! their breadth upon the sashes to exclude it.j Figure 5.—Flan and section of the lower sash-shutters
j and boxings of a common window, showing the nature ofthe work.
Window-Shutters, the wooden doors by which windowsare occasionally closed, or secured. See Boxings , Joinery,j and Sash-Frame.
WING, the outlying and returning ends of a building.
| WITHS, (from the Saxon,) the partitions of flues. Seej Chimney .
| WOOD, (from the Saxon, toude,) a fibrous material, of| the greatest use in building, formed into shape by edge-tools.
J For a description of the different kinds of wood as applicablej to building, see the articles Timber and Material ; and for
the method of measuring it, see Mensuration , towards theend. See also Seasoning of Timber, and Strength ofMaterials .
Wood Bricks, blocks of wood cut to the form and size ofbricks, inserted in the interior walls of apartments, as holdsfor the joinery.
WOODEN BRIDGES , are platforms constructed of carpen-try, for crossing streams, rivers, roads, &c. These bridges maybe looked upon as the origin of all such constructions, whetherof stone, wood, or iron. In early times, it may fairly besupposed, that trees, or planks made from them, would bethrown from one bank of the stream to the other, so as toserve for a footway, by which a passage might be effected.This might have been suggested in the first instance byaccident, either by a tree falling in that position, or elseby its growing across a stream, as sometimes happens withwillows, &c. A plank placed from one bank of a stream toanother, is the simplest form of a timber bridge ; it is at thesame time the most perfect; and the principle on which it > ssuspended, or kept in its proper position, is worthy of con-sideration, for we may learn how to construct the best andmost advantageous kind of bridge, suitable for immensespans, from this unpretending, and apparently unpremeditatedcontrivance.
When a strong plank is thus laid upon two supports, thatpart of it which lies midway between them, has to sustain h®own weight, together with the transit-load which it has tobear, such as that of anything crossing over it, by the cohe-sion between its particles, for as that part of the plank hasnothing to rest upon, it is therefore clear, that it has a t® 11 'dency to break somewhere between the points of supp 01when the strain becomes very great upon it ; but owing ,0
this cohesion of the particles, which attracts them to
one
weight upon
technically termed, to sag, but in order tonecessary that the fibres on the under sideshould first be drawn out, or lengthened, that is,while on the
another, such a plank cannot snap asunder, because the fibre®of the timber of which it is formed, are so interwoven, tin*one particle or atom of the material will not readily 11separated from its fellow, as long as such material remain®in a sound stale. This being the case, the effect of t* 1the beam will cause it to bend, or what
but in order to this, it ,
of the beam
’ subjeCt ier
a tensile strain, while on the contrary, those on the uppsurface will be forced to contract, or become shorter, in 0 ^words, they will be pressed upon longitudinally, andsubjected to a compressive force. It is also evident, ^there must be some intermediate plane between theand lower surfaces of the beam, where the two opp« s,le jj[tending forces will meet, in which, of course, neithe* ^preponderate ; this, which is denominated the neutral P ,x ^ eis situated lower or higher, according to the depth o ^beam, the homogeneity and cohesion of the material ot ^it is composed, and a variety of other consideration®^^a general formula for finding the weight with which it . ^be advisable to load such a beam, we may give the tot
2bd 1 s , . . gi, which f* 10
w = —— where w is the weight in lbs. witn v '*
3 1 •. If, h itS
beam may be loaded, including that of the beam ltse ’ t j t in
breadth in inches, d its depth in inches, l h® J fc c alcU'inches and s some known constant, representing 1 ter jai,lated strength of the kind of timber, or other ^ gyO,employed. That of larch has been estimate ‘ 415,Riga fir at 376, English oak 400, Mar I m j, (j'o,red pine 447, pitch pine 544, Canadian oak 5 8 » a n ( theteak 820. When the inertia of such abridge u poi> 9deflection, or sagging, of the beam is found to dep