Details
Interchangeable chromotrope
A 7 x 4½ inch wood-body chromotropic slide with hand-crank and removable retaining collar; twelve 3-inch diameter glass chromotropic pairs in wood box; a wood box holding three 3-inch diameter glass chromotropic pairs, five pierced foil discs and two others(a lot)
A 7 x 4½ inch wood-body chromotropic slide with hand-crank and removable retaining collar; twelve 3-inch diameter glass chromotropic pairs in wood box; a wood box holding three 3-inch diameter glass chromotropic pairs, five pierced foil discs and two others(a lot)
Further details
See illustration