Perspective and geometrical drawing adapted to the use of candidates for second and third-class teachers' certificates (1887)
McGuirl, Thomas H. [from old catalog] · Toronto, W. Briggs; · leaf 131
Fig. 97. JTo. 25.—To draw a tangent to an ellipse (a) from a pointin the circumference. … Fig. 98. GEOMETRICAL DRAWING. 127 Let B, C be the foci and A, given point on the curve; joinBA and CA and produce them to D and F; bisect the angleBAD by AK, and the angle DAF by AG. Then will KA bea tangent and GA a perpendicular or normal to it, at thepoint of contact, A. (Fig. 98.) (b) From an…
Geometrical drawing · Perspective
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