Richey's guide and assistant for carpenters and mechanics : a work of practical information, giving almost every geometrical and practical problem likely to arise in the work of the carpenter, and quick and easy methods for their solution : the use of the steel square, etc., tables showing strength and weight of materials, methods of framing, useful recipes, etc., etc. (1894)
Richey, H. G. (Harry Grant), b. 1868 · New York : W.T. Comstock · leaf 48
43—To Draw an Equilateral Triangle when thePerpendicular is Given.—Draw a b for the perpendicu-lar. Fig. 46; then draw c d a.nd £ h at right angles to a b;then, with any radius and a as centre, draw the semi-circle,
Carpentry
Internet Archive · Boston Public Library · Public Domain Mark 1.0. Free to use for anything.