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his words are, “ The upper arched one I take to be of greatstrength, though the trusses are inverted; for the pressurebeing upon an arch whose butment is good, I think a greatweight can no way occasion the bending of the girder.”

We come now to the British Carpenter. Though Mr.Price’s order of treating his work is not so regular as themethod adopted by Smith, his descriptions and observationsare very correct; and, with the exception of a few references,there is hardly anything wrong.

This author begins with the scarfing of beams, as repre-sented in Plate V. of our Work, Figures 1, 2, 3, 4, 5, 6. Hesays that the methods shown by the diagrams 3, 4, 5, 6, arethe strongest; perhaps in consequence of their being tabledinto one another ; and that represented by Figure 6, has thisproperty, that the pieces may be put together without anywaste at the ends; he observes, that it is not his intention tolimit the lengths of these scarfings, but only to show the man-ner of tabling the pieces together: he might also l>ave said,that though nothing determinate with regard to the lengthsof scarfings could be done, the greater the extent of thejoint in the direction of the fibres of the beam, the more willit be disposed to resist separation, though there will be agreater waste of timber. Those represented by Price aremuch superior to those in Smith’s work.

He then describes the method of trussing girders of greaterextent than 24 feet, as we have shown in Figures 7 and 8;and proposes that the pieces which are to constitute the corebe made of good dry straight-grained English oak, 4 inchesby 3, or 6 by 4, as the strength may requite, and let half intoeach piece ; the pieces of the core being inserted in the onehalf, so as to abut firmly at the ends, and the two flitches puttogether so that the internal braces may abut firmly at theends of the other flitch, and then bolted together, will com-plete the girder ; he prefers that of Figure 8, to Figure 7, as,being divided into three parts, it raises the pitch of the braces,and though the middle part is left untrussed, it may be lookedupon as an inflexible solid, as the proportion of the breadthto the length is reduced much nearer to a ratio of equalitythan the dimensions of the whole beam, the depth being thesame in both cases. The flitches, he observes, may be mor-tised through at the lower end of each truss, and the coretightened by wedges driven therein. Girders constructed inthe manner of these two examples are much better calculatedto perform their office, than those before given by Smith,which are void of every principle of mechanical science.

This author then speaks of the method taught by Alberti,as follows :—“Take two pieces or flitches, being well dried,and turn the but end of the one to the top end of the other,without trussing at all, and bolt or screw them together.”

Mr. Price then proceeds to the various joints in roofing, asin Figure 9, which represents the junctions of the struts andprincipals with a king-post.

Figure 10, is another mode, which he uses where thebreadth of the bottom of the truss-post will not allow a right-angled abutment to the direction of the strut: he makes theangle on the end of the tenon, with good reason, equal to theangle made by the shoulder, but on the contrary side, so thatthe two abutments may contract each other’s efforts in movingthe strut up or down on the side of the said post.

Figure 11, represents his method of forming the end of thetie-beam and lower end of the principal, so as to form a jointwith double mortise and tenon, which, he says, presentsgreater resistance than when made with single mortise andtenon.

Figure 12.—No. 1 and 2, show the proportion which themortise or tenon ought to have to the breadth of thestuff, either for the joints of roofs or truss partitions, by

making the tenon or the mortise one-fourth of the breadth ofthe whole, and keeping the mortise and tenon in the’middle.

Figure 13. No. 1 and 2, another mode for the same pur-pose, not much in request at the present time.

Figure 14. No. 1 and 2, the manner of joining the binding-joists and girders in floors, the same as used in the presenttime, with a tusk or sloping shoulder, and the double resist-ance or butment.

Figure 15. “No. 1 is called a bridging-floor, as beingframed with a binding or strong joist in every three or fourfeet distance, and flush to the bottom of the girder, so thatwhen the house is covered in, you pin down your bridgingsthereon, and flush with the top of your girder; and this is thebest way of carcase-flooring.” The section of this floor takentransversely across the binding-joists is shown at No. 2,Figure 15. Mr. Price observes, that the best way to laygirders, “ is i not to lay them over doors or windows, nor to°near chimneys; and, at the same time, to have the boards heall one way and hence the oblique position of the girder, ashere represented, is occasioned by the fireplace.

Figure 16. No. 1, a carcase-floor with single joists, ° rwithout bridging-joists. These are framed flush with thetop of the girder, “and have every third or fourth joist thedepth of the girder, and those between more shallow.” No. 2shows the ends of the joists, and the ceiling-joists framedinto the deep joists. No. 3, the sides of the deep joists, wid 1the pulley-mortises, in order to receive the ceiling-joists.

Mr. Price then proceeds to lay down the sides of roofs > Dpiano, and shows the backings of the hips in the same man'ner as has been detailed by Godfrey Richards in the forfflC rpart of this article, according to Pope ’s principle.

We shall here transcribe one of his examples, in which heattempts to show, for the first time, a method for finding th ejoints of purlins upon hip-rafters: his process, which isfollows, is tedious; his diagram and explanation are botnobscure and defective, but show some novelty of form angeometrical skill in lines. ,

“ Admit the plan (Plate VI., Figure 1, No. 1) was requh' e ^to be enclosed with a hipped roof: first, find the middle t 0it, as f; then draw the bases of your several hips, as afcf df, and e f; resolve on some pitch or height, as in N«; ’at f g ; to. this section bring all the bases of your respect!hips, as the letters of reference show; this gives you *length of each respective hip; therefore, from the sect 10No. 2, you describe the skirts round the plan No. 1, as obeg, c dg, deg, and e a g, which form the roof require**" t

“ To find the back of any hip, do thus : Draw a linepleasure, crossing the base of the hips at right angles, as 1line h i, which crosses the base of the hip cf; observeit passes through the sides of the plan; on the base linethis hip, raise its section from No. 1, as c gf; lastly, P a g[1one foot of your compasses in the intersection, as at y > °P .the other foot, till it touch the hip eg at its nearest distandraw a small section till it cross the base, as at k; s °- eS ihkki the back of that hip ; and is the most exact, and eai ‘ eC jmethod that ever was delivered for this purpose ; the shadowpart, o, is the section of the supposed timber the hip ^shaped out of, being cut off at right angles with its s *^ e . a c )rbadk. What is said of this explains the hip af, whose u*is Imn, and its section p is shaped so as to have the P 111 ^^come square against it; the letters of reference showrest.” ... h p be

“ To find the side joint of a purlin (in case thenot shaped as above) so as to cut it by a templet, su PP oi ^ gl -there be no room, or occasion to frame it into the hip-'fexample, take any two hips from the plan No. 1, as ej