The American house-carpenter; a treatise on the art of building, and the strength of materials (1867)
Hatfield, R. G. (Robert Griffith), 1815-1879 · New York, J. Wiley · leaf 63
118.— To desaHbe an ellipsis by intersection of lines. 7 Lo.% 50 PRACTICAL GEOMETRY. a b and c d, {Fig. 83,) be given axes. Through c, draw / ^,parallel Xc ah ; from a and 6, draw a f and h g, at right anglesto ab ; divide f a, g b, a e and e 6, each into a like number ofequal parts, as at 1, 2. 3… … Where neither trammel nor string is at hand, this, perhaps, isthe most ready method of drawing an ellipsis. The divisionsshould be small, where accuracy is desirable. By this method,an ellipsis may be traced without the axes, provided that a diame-ter and its conjugate be given. Thus, a b and c d,…
Carpentry · Architecture
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
