Descriptive geometry for students in engineering science and architecture; a carefully graded course of instruction . e so nearly 76 SECTIONS OF SIMPLE SOLIDS 77 perpendicular to XV these points are carried by level lines to the slant edge inwhich a occurs and from their plans in the plan of this edge they are carried byarcs to their proper places in the plans of the edges they belong to, and thenceby perpendiculars across the line to their rabattements. The true formmay now be drawn and is marked in the figure by hatching. In Fig. 79 a right circular cylinder has a section plane perpendi
Descriptive geometry for students in engineering science and architecture; a carefully graded course of instruction . e so nearly 76 SECTIONS OF SIMPLE SOLIDS 77 perpendicular to XV these points are carried by level lines to the slant edge inwhich a occurs and from their plans in the plan of this edge they are carried byarcs to their proper places in the plans of the edges they belong to, and thenceby perpendiculars across the line to their rabattements. The true formmay now be drawn and is marked in the figure by hatching. In Fig. 79 a right circular cylinder has a section plane perpendicular to , passing through it in such a way as to cut the top horizontal surface and cutalso a considerable amount of its cur\ed vertical surface. Since the section shapeof a right circular cylinder by a plane inclined to its axis is an ellipse, the result inthis case will be part of an ellipse, as the shape of the section. Points in the curvedoutline of the true form are obtained by choosing straight generator lines, as theyare called, on the curved surface of the cylinder, marked in this example at a, b. c, d, c, etc. Portions of the elevations of these generators are shown in order toobtain the elevations of the intersection points to be rabattcd. In the figurethe shape of section is shown covered with hatching. In Fig. 80 a right circular cone has a section plane RST passing through it,and since this plane cuts all the generators of the curved surface it produces anellipse for the shape of the section. This shape is rabatted on to the byusing 5 as centre. Generators, taken in such places as will give a good distribu-tion of points in the curve, are drawn at a, b, c, d, e, etc. These in elevation areseen to be cut by the section plane, and the points in which they are cut are carriedover by arcs to the It is necessary to locate them in plan, which is straight-forward work except in the case of generator bb. The point in this generatormust be carried horizont
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisheretcetc, bookyear191
