The power of form applied to geometric tracery : one hundred designs and their foundations resulting from one diagram (1851)
Billings, Robert William, 1813-1874 · Edinburgh ; London Published by the author by William Blackwood and Sons · leaf 125
The radius of Nos. 1,2, 3, is the diameter of the enclosing circle. xcvi. … The radius of 3, 3, is the diameter of the outer circle. of the same radius. Nos. 4, 5, are curvea
Decoration and ornament · Geometrical drawing
Internet Archive · Getty Research Institute · Public Domain Mark 1.0. Free to use for anything.
