Practical engineering drawing and third angle projection, for students in scientific, technical and manual training schools and for ... draughtsmen .. (1897)
Willson, Frederick Newton, 1855-1939 · Princeton, N.J., The author · leaf 55
t the vanishing line does not cut the base and, evidently, no Hnefrom S to the base would be parallel to the lower plane; but the latter would cut all the elementson one side of the vertex, giving the ellipse. 149. Bearing in mind that the projection of the circle A H B t is on the lower plane… … occurring about cr ^ in a manner exactly similar to that which would occur were i oj c a system offour pivoted links and the point o pressed toward c. The motion of S would be parallel and equal CONIC SECTIONS AS HOMOLOGOUS FIGURES. 4& to that of 0, and, like the latter, would evidently…
Mechanical drawing · Lettering
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