. Stereotomy : Problems in stone cutting. In four classes. I. Plane-sided structures. II. Structures containing developable surfaces. III. Structrues containing warped surfaces. IV. Structures containing double-curved surfaces. For students of engineering and architecture . the conicalwall. Their heads are in vertical planes parallel to VGT. The coping joints. — These simply divide the top of thecoping suitably, so as to break joints with the upper stonesof the wall, and are in vertical places through the elements KL — KL, MN — MN, etc., of the top ofthe coping. Thus, MN —
. Stereotomy : Problems in stone cutting. In four classes. I. Plane-sided structures. II. Structures containing developable surfaces. III. Structrues containing warped surfaces. IV. Structures containing double-curved surfaces. For students of engineering and architecture . the conicalwall. Their heads are in vertical planes parallel to VGT. The coping joints. — These simply divide the top of thecoping suitably, so as to break joints with the upper stonesof the wall, and are in vertical places through the elements KL — KL, MN — MN, etc., of the top ofthe coping. Thus, MN — MNPQ, LK — LKKL, etc., are verticaljoint surfaces of the coping. 6°. Location and limitation of the face joints. — It is desirablethat a coursing joint should coincide with the to£ of the pier,but not always convenient to make a suitable common divisorof the heights of the pier and wall; hence arises the problem :to arrange the stones in courses of diminishing thickness up-wards, and so that a coursing joint shall coincide with the topof the pier. Now parallel lines will be divided proportionallyby lines which meet at a point, P ; hence, if the latter linesdivide a given line, A, equally, they will divide a line, B, notparallel to A, unequally. ll. IV. 5 J^^ 3^1 UB SoitZ. SuJO. SoJL s. ir« 1>, STONE-CUTTING. 89 Hence, choosing in this example five courses of stones, as-sume any point as a on the level ab of the pier, drop a per-pendicular BB from B, and draw aB and aB. This done,adjust any convenient edge scale of equal parts, by trial, tillthe 0 of the scale being placed on aB, the point 1 of the scaleshall fall on ab, and 5 of the scale on aB. Holding the scalein this position, prick off the other points of division from 0 to5 upon the paper, and draw lines from a through the points sofound, to meet BB, as at y, etc. Then, through y, etc.,draw the horizontal joints. To avoid acute intersections of the coursing joints, qp, etc.,with the top edge, aB, of t
Size: 1807px × 1382px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, bookidstereotomypr, bookyear1875
