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 137
lling lines, o b and p.b. (b) The length of any tangent, as m 6, is thatof the helical arc m a on which it has rolled. (c) The horizontal projection b q of any tan-gent b m equals the rectification of an arc a q which is the projection of the helical arc from the initial point a to the point of… … * For full treatment of the involute of a circle refer to Arts. 186 and 187. t This relation is due to considerations of curvature. At any point of any curve its curvature is its rate ofdeparture froni its tangent at that point. Its radius 0/ curvature is that of the osculatory circle at that…
Mechanical drawing · Lettering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
