Practical engineering drawing and third angle projection, for students in scientific, technical and manual training schools and for ..draughtsmen .. . urve. A plane perpendicular to the axis of cuts the latter in a right section. The bases of right cones, pyramids, cylinders and p)rismsfulfil this condition and require no special construction for their determination; but the developmentof an o):ili(jue iorm usually involves the construction of a right section and tlien the laying off ona straight line of a length equal to the jjerimeter of such section. Should the right section Ije a
Practical engineering drawing and third angle projection, for students in scientific, technical and manual training schools and for ..draughtsmen .. . urve. A plane perpendicular to the axis of cuts the latter in a right section. The bases of right cones, pyramids, cylinders and p)rismsfulfil this condition and require no special construction for their determination; but the developmentof an o):ili(jue iorm usually involves the construction of a right section and tlien the laying off ona straight line of a length equal to the jjerimeter of such section. Should the right section Ije acurve its equivalent length on a straight line is called its rectification, which should not be confoundedwith its develojmient, the latter not Ijeing necessarily straight. 414. The development of an oblique pjrisni, when the faces are equal in tvidth. In Fig. 249, anoblicjue, hexagonal prism is shown, with x for the width of its faces. Since the perimeter of aright section would evidently equal 6 x we may directly lay off x six times on some iierfjendicular .,=!„„- a A B E H t s»== ~S! d ^ tl I 3 C F C 3 Ai Taking the same prism as in the. a f 152 THEORETICAL AND PRACTICAL GRAPHICS. :Fig-. 3-^9.
Size: 2921px × 856px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjec, booksubjectlettering
