Practical plane geometry and projection Volume 1; for science classes, schools, and colleges - Softcover

Inhaltsangabe

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1880 Excerpt: ...those points above the same plane, but will indicate at Ax and Dx the relative positions (on BC produced) of the feet of these perpendiculars, i.e., their intersections with the plane of the rectangle. Construct the points Dx and Aj into the plane I'mn, as shown at 'D" and A", and at each of the points, D", c, b', and A", draw perpendiculars to the v. t.--I'm. These lines will be the projections on the v. p. of the perpendiculars previously spoken of. Then Djrf, Cc, B6, and Aja, drawn perpendicular to the h. t., will be the indefinite projections of the same lines upon the h. p. Now, as these perpendiculars to the plane I'mn are necessarily parallel to the v. p., the points, d', e', f, a, are readily obtained on the elevations, for their respective heights above the plane of the rectangle are shown on the auxiliary hexagon previously described, i.e, DV is equal to D1D, etc. The plans of these points can then be determined from their elevations. The projections of the hexagon at the other end of the solid could be determined in the same way; but as the long edges are equal and parallel, their projections also must be so; and further, as two of these are already determined (ch, c'h', and bg, b'g'), lines parallel and equal to these, through the other points of the hexagon, abcdef, will enable the student readily to finish the required plan and elevation. The principles regulating the dotting of the hidden edges, are applied as explained in a previous problem.. 2nd Solution. In Plate XXVII., fig. 2, the above problem is solved by a different method to that just described. The construction, in so far as finding the traces of the plane of the face, whose sides are given, and the projections of the figure, is the same. But in the building of t...

Die Inhaltsangabe kann sich auf eine andere Ausgabe dieses Titels beziehen.