blue springs, purple drills
Faint Yellow — Cutters.
Straw Color — Bone Tools.
Yellow — Ivory Tools.
Deep Yellow — Milling Tools.
Yellow Orange — Boring Tools.
Orange — Wood Chisels.
Red Orange — Taps.
Red — Plane Irons.
Red Purple — Gouges.
Purple Red — Gimlets
Purple — Drills.
Purple Blue — Chipping Chisels.
Blue — Springs.
—
ex drawing in
Joshua Rose (ca1845-1910 *) and Park Benjamin (1849-1922 *)
US Patent 205,578, Improvement in Chromatic Tempering-Scales (1878)
same, elaborated
tags:
chromatic; classification; tools; yellow
Park Benjamin; Joshua Rose