The art of double-counting on the lathe : whereby a variety of patterns in the form of ellipses, triangles, squares, pentagons, hexagons, and octagons, 3, 4, 6, and 8-looped figures, besides others of a more complex character, may be produced by means of the common eccentric chuck, used in combination with the division-plate and the eccentric and elliptical cutters
An 1857 London treatise by James Ash, published by L. Booth, explaining how to produce geometric rosette patterns on a lathe using eccentric chucks, division-plates and elliptical cutters, written for turners and mechanical engineers. Its plates show engine-turned ornament built from looping curves, and a designer could borrow the layered rings, rosettes and frame-within-frame compositions for guilloche-style borders and decorative panels.
