Apparatus: A New Colour Mixer and Episcotister

The paper describes the construction of a differential system which can be used as a colour mixer or flicker apparatus. The use of sectored discs has been largely replaced by filters, wedges and polaroids in much visual work. However, our apparatus has two main applications, as a convenient, inexpensive colour mixer for student work and as a research tool in the study of flicker fusion and kindred phenomena.