L. E. Knott Apparatus Co. Single Axle Color Mixing Apparatus

This device used a large pulley turning a small pulley to increase the rotational speed of a stimulus wheel beyond what could be achieved by direct hand rotation. Wheels with different combinations of colors were used to demonstrate the principles of color mixing. Wheels with black and white patterns were used to demonstrate motion aftereffects and to produce colors using Bentham's patterns. It was manufactured by L. E. Knott Apparatus Co., Boston, Mass.