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ob ac ene( 3> and the work will stand well; but it must beits ?f'' Vec ’ ^ lat > as tPe wood has a natural tendency to unbende > the curved surface, upon which it is glued, should betnewhat sharper than that intended to be made, to allow forthi « tendency.

Ve ° me w °rkmen form a hollow cradle, and bending thePro 661 ? * nto confine their ends with wedges, which com-'vitf 8 t leni together; and by a very small degree of rubbing,out * c * illm mer made for the purpose, the glue will be forcedof the joint.

sui-r E1Hod II*—Form a cradle, or templet, to the intendedc . e > an <l lay a veneer upon it; then glue blocks of woodto n lts back, closely fitted to its surface, and the other joints°f tlj ot ^ ler > the fibres of the blocks corresponding to those

veneer.

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it Th ? d HI*—Make a cradle, and place the veneers uponVe Con ® n ‘ n g one end of them; spread the glue between theetl( j 3 ers with a brush, and fix a bridle across, confining itsPut 8 i ei ^ ler hy nails or by screws; open the veneers again,bri ii Ue a sec ond time between each two, and fix anothere across them; and in this manner proceed to the otherextl 'emit y .

th^) ETa0D I^-—Run a number of equidistant grooves acrossonlv aCa th e board, at right angles to its edges, leavingCr adl <a Sma ^ thickness towards the face; bend this round asi;' e > with the grooves outwardly, and fill the grooves withPlan a wood, which, after the glue is quite dry, are to behe snr ° Wn t0 t ' le surface of the cylindric board, which mayIn , n , e< I hy gluing canvass across the back.

n la l tlstea( I of using a grooving-plane, workmen frequently"'hen w ’ l h the saw ; but this mode ‘ '

fi • w oaw f uut tms muuc is not so strong

H) 1( j ,. ltUs hed, as the uncertainty of the depths of the kerfs.u n „ difficulty of inserting the slips, wilUoccasion a very

iTo A curvature -

(i n?/ °end a board, so as to form the jrustum of a cone, orof ^^mental portion of the frustum of a cone, as the soffitcover' 6 bea d of an aperture .—Find the arch-form of thehoard' 0 ®’ as s h°wn under the article Envelope ; cut out aa C r 0Ss *° t h' s form, and run a number of equidistant groovesBlade t' 1 ’ ten d‘ng to the centre : this being fixed to a templetin t] ,° '•he surface of a cone, finish it in the manner shownTo A* 8 *' mel: hod for a cylinder.

a n, , ew< * hoards so as to form a spheric surface. —Makepl ail o '° fhe covering of a given portion of the sphere inher of 08 s h°wn under the article Dome ; complete the num-great . staves by this mould ; make a templet or mould to aat rir,} 0 . 0 ^ 6 l he sphere ; groove each of the staves across,bend it an 8^ ea t0 a h ne passing through the middle, andthe ed roun d the templet; put slips in the grooves ; shootcentre f S 'he staves, so as to be in planes tending to theWin fv, ° 'he sphere ; and these staves, being glued together,To * a s Pheric surface.

frusta ^ U P ^ te s h a ft of a column, supposing it to be thecircutf ° f a cone .—Prepare eight or more staves, as theSn h,-‘o. n . ce / na y r e< i uire - in such a manner, that if the co-^hich d‘ Ute .d> the joints may fall in the middle of the fillets,'he tv. i Positio n will be stronger than if they were to fall ine of the flutes.

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shaft of Suppose eight pieces to be sufficient to constitute theend • a i 3 C0 ' u Hin : describe a circle to the diameter of eachcon c ’ out each circle circumscribe an octagon; from thea n int er 86 eac h angle draw a line to the centre ; then draw°f the '° r conce ntric octagon, with its sides parallel to those?r ara llel C sL, C p T! C ^ in g one, the distance between any two'he thick' 1 6S ’ on 'he same side of the centre, being equal tos ' a Ves vv'llT stu ®' intended : and thus the sections of thehe formed at each end, and consequently the bevels

will be obtained throughout the whole length ; any two pieceswhen joined together having the same angle, though the stavesare narrower at one end than at the other.

In order to join the column, glue two pieces together, andwhen quite dry, glue in blockings to strengthen them ; join athird piece to the former two, and secure it also by blockings.In this manner proceed to the last piece but one.

In fixing the last, the blockings must be glued to the twoadjacent staves, and their surfaces, on which the last stave isintended to rest, must be all in the same plane, that its backmay rest firmly upon them. In closing up the remainingspace, the part of the column that is glued together should bekept from spreading, by fixing it in a kind of cramp, orcradle, while driving the remaining stave to close the joints.

Instead of this mode, some glue up the column in halves,and then glue them together.

When it is necessary to have an iron core, to support theroof or floor, the column must be glued up in halves; in thiscase, the two halves are to be dowelled together, and thejoints filled with white-lead. Instead of a cramp, a rope isused, twisted by means of a lever. In the act of bringingthe two halves together, the percussive force of the malletmust be applied upon the middle of the surface of one half,while an assistant holds something steady against the middleof the other, that the opposition may be equal ; and by thismeans, the surfaces will be brought into contact, and formthe joint as desired. In this operation, pieces of wood oughtto be inserted between the rope and column.

To glue up the Ionic and Corinthian capitals for carving.—The abacus must be glued in parts, so that their joints maybe in vertical planes. The leaves and caulicoles of the Cor-inthian capital may be first made of rectangular blocks, andfixed to the vase.

To make a cornice round a cylindric body of the leastquantity of wood, when the body is greater than a half-cylin-der, and when the members will nearly touch a right lineapplied transversely. —Draw a section of the cylinder throughits axis, and let the section of the cornice be representedupon the cylindric section. Draw a transverse line, touchingthe two extreme members of the cornice ; and parallel to itdraw another line within, at such a distance from the former,as may be necessary for thickness of stuff; produce the latterline, till it meet the line representing the axis of the cylin-der, and the junction will either be above or below, accordingas the cornice is applied to the convex or concave sides ofthe cylinder. This meeting is the centre of two concentriccircles, whose radii are the distances between the nearest andfarthest extremes of the section of the cornice. This is evi-dently an application of the method of finding the coveringof a cone. When mouldings are got out in this manner, viz.,by a piece which does not occupy the space, when set to theplace represented by the height and breadth, they are said tobe sprung.

When a cornice is to have much projection, the corona, ormiddle part, is got out of a solid piece, and the parts aboveand below, or one of them, as may be found necessary, onlyset to the spring, and supported by brackets.

Another method is, to bend veneers round the cylindricsurface or surfaces ; then work them to their form withmoulding planes.

Raking mouldings depend principally upon the nature ofa solid angle, properly called a trihedral. In a trihedralangle, with two of its planes at right angles to the third, letthese two former make an obtuse angle ; then suppose amoulding placed in the concourse of the two planes whichform the obtuse angle of the solid, and another in the con-course of the two planes which form one of its right angles; i