This article was originally published with the title “ An Instrument for Drawing Ellipses and Hyperbolas ” in Scientific American Magazine Vol. 97 No. 26 (December 1907), p. 472 doi:10.1038 ...

Accurate design of an ellipse, parabola and hyperbola all require great competence in mathematics. The design appears to incorporate a 3,4,5 triangle. The hyperbola, ...