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Pri^ e - re tlle text is unintelligible, and the discovery of tliecopies, by inspection, still more so.

Co ass * n g from the The Builders Complete Assistant, wejy e next to The Builder’s and Workman's Treasury ofWh* h *’ ^ the same Author. The portion of this workeri , c ^eats of carpentry, is contained in an appendix at thej c 9nsisting of fourteen plates.are ^J 'ute XI. Figures 1 and 2, Nos. 1,2, 3, of each Figure,Uo t)°' Vn two methods of lengthening beams: but there isth e ° j description than what is exhibited at the top ofex I v ate > n viz., “ The splicing or lengthening of beams

^eth tW ° P * eces are tabled together, by a very differenta re c 0<1 1° what-any former author has exhibited. The tablesas j n °!l cea ^ e d, showing on the outside, when bolted together,Constr- ^ eac ^ figure, an oblique continued joint. Theout br* 10 !- 1 ' 011 ' S * n o etl '°u3, as it prevents their separation with-cuit y re ,. n g tke tables by a longitudinal strain; but the diffi-proc es ° dtting them together with accuracy, and the tediousL an s> . re uders them unfit for practice.t° thog s Geometrical Principles of Roofing are similaring ^ 6 op the preceding author; but for the sake of show-of treat• tennS a PPfi ca td e to different purposes, and his methodtions : «“ g , he subject, we shall extract a few of his descrip-tral li n a ^fd {Figure 3) plan of the raising; ef the een-a g, g c J } m ’ l °j base lines of the outward principals ;k n bag’ ^ d, base lines of the hips; g h base of the ridge;fineg 0 j. fi ne of the middle pair of principals; eg, hf, basePoi nts the single principals, which meet the hips in theteeeivg ^ ^ m no, dovetail mortises in the raising, to(Pfure im ^ ovet fHs or cauhs 1, 2, 3, of the beams ABC;a s p t ~ p) P P> dovetail mortises to receive the angle-braces,fi° v etail. m * 9,M r e d, a caul? or dovetail at large ; e, theCa Uk d ,, rQort >ses in the raising, to receive the dovetail or

° au ked q “ a b c d, plan of the raising;/ g,fg,f g, beamsCau ked d 0 ° Wn . °u the raising ; p p, p p, &c., angle-bracesre ceiv e t >' Vn „ lrl bke manner; a e, b e, c e, d e, dragon-pieces toJeffers ; f ee t °f the hip-rafters ; a h,b h, c h, dh, hip-tbe fo 0 t f’’ tbe angle at the top ; and hah the angle ofFigures' ,« hip ah '"

° r irregnj ' , '* Th find the angle of a hip in any regular38 c > draw a -ding. —Rule. On any part of its base line,^ ^ 6, an j line at right angles, as f g ; set up the hip,

^ c e en r ? m c ^ raw c d perpendicular to the hip h b;^ e /e o is+u to c ^ an ^ draw the lines f e, e g ; then theThese deso • 6 , an S^ e of the back required.”s ®d by bi m ripti °us are tolerably clear ; the technical termsp. l1lc ipals y do are . raisin 9> base-line, hips, back of the hip,:/ Ces . RaiJ' eta ^' mor ^ es ’ eau ks, angle-braces , and dragon-1, Se *> but is ' 8 use( l by Moxon, in his Mechanical Exer-°f the fi e fi ne< t by that author ; base-lines, hips,

a' , lar( ls, j n J?’ an< f principal rafters, are used by GodfreyIan, back ino- s f 0r f lruct ions of Roofs, in finding the lengthsLa* 06 ? tke dia° iP-rafters. This last-mentioned author^ call s fu Da ^ keams under the hips, dragon-beams;°bs *’ ^''ice SDpl , em dragon -pieces. What Langley spellsO*. na P , 8 cocks. Angle-braces are not, that we havejjj„ jo-ck-mft an 7 author before Langley, who also■pf Fr easiln ers ’ ln Hate 5, of his Builder’s and Work-S<1 is a

10 haT^ ^kley 01 *’ 1 j°- t ment ioned in the list of authors, byheiop. ® st ood even i tect ’ w hich, in point of priority, oughtX'i S g uated i n J . ore Smith’s Carpenters Companion, ite 'fition' lbb8 hed hw w^ e 'P a = e 1^30; another work was like-°f Whi c b as ^fi' var< l Hoppus, Surveyor, the second’ a Ppears from the title-page, was published j2 D

in 1738; when the first edition was published we do notknow, but probably about the same time as Oakley’s, orbefore. With respect to carpentry, these two works are nearlyalike, as to the number of the problems, their order, themethod of treating them, and the end intended; one seems tohave been copied from the other, and the first of the twoto have been taken from Halfpenny’s Art of Sound Building,with the exception of a problem, which is exhibited in a plate,and explained in, each of these authors, for covering of thehead of a niche or dome, with boards, to bend with theirjoints in vertical planes, passing through its axis. This pro-blem is thus explained by Oakley:

Figure 6. “ To make a niche or globe, with thin boards ;or to cover them with paper or pasteboard. —Admit a f j(No. 1) to be the plan of a semi-circular niche ; c ef d (No. 2)to be the board, paper, or pasteboard, of a given width, c dor ef. Divide the semi-circle a f l into equal divisions, accord-ing to the breadth of (No. 2) usab, b c, c d, de, eg, g k, h i, i It,and hi; draw the lines, b u, c u, du, eu, g u, h u, i u, h u,and let fall perpendiculars on the line a l, from the pointsb, c, d, e, g, h, i, k. Upon the centre u, with the intervals,m, o, r, and t, describe semi-circles; set the girt of the archaf or / 1, on the board, g c, (No. 2) as ca and d b, whichdivide into so many equal parts as there are semi-circles, as in(No. 2.) Divide (No. 2) in the midst, as by the line uw;take the arch a b, and set it equally on each side of the lineuw, as at a b ; set the arch m n, in like manner, on u w, asat m n, and so on to t s ; then by sticking in small tacks at.the points a, m, o, r, t, and u, on the one side of u w, andat the points b, n, p, q, and s, on the other side of u w, byapplying a thin ruler from a to u, and b to u, the curve lineson each side will be given, which maybe described by a pen-cil, &c., which is the true mould for every piece in a globe orniche, which was required.”

Here it must be observed, that the division of the semi-circle (No. I) is erroneous; for if the quadrant af or/ 1 beconsidered as a vertical section of the dome, it is evident itshould have been divided into the same number of parts asthe length of the board (No. 2;) and the several lengths ofthe one equal to those of the other; but a f or f l is onlydivided into equal parts, while the board is divided into5; which inequality causes the board to be too narrow towardsthe top, and to swell out too much at the bottom, as shownin the following figure.

In The London Art of Building, written by Salmon, thereis nothing new in construction. His geometrical principlesof roofing are like those by Godfrey Richards; besides which,he treats of no other subject, except a few designs of roofs.

The British Architect, the production of Mr. AbrahamSwan, is not very abundant in curious constructions of car-pentry, yet there are some ideas worthy of notice.

Figure 7, No. 1, “ Shows the backing of the hip.” “ Dividethe thickness of the hip into two equal parts; then havingfound the pitch of your hip, as is shown in (No. 2) set one ofthese parts upon the base line, from b to a, and it shows whatwood is to be taken off.

“ If the side of the building comes in with a bevel, as thedotted line h, in (No. 1) then transfer half the thickness ofthe hip, from d to c, in (No. 3) and take the distance/ e, in(No. 1) and set it from c to g, in (No. 3.) This will show howmuch is to be taken off the hip, when the building bevels.”

It is strange that this author should have departed so farfrom Pope ’s scientific method, as first shown by GodfreyRichards, in order to adopt one so mechanical, more liable toinaccuracy, and less expeditious.

With respect to groins, all that Swan has said on this sub-ject, is contained in the following words;