Sound and light were transformed into mechanical action at the banquet of the National Tool Exposition recently to illustrate their possibilities in regulating traffic, aiding the aviator, and performing other automatic functions.

A beam of light was thrown on the “eyes” of a mechanical contrivance known as the “telelux,” a brother of the “televox,” and as the light was thrown on and off it performed mechanical function such as turning an electric switch.

The contrivance, which was developed by the Westinghouse Electric and Manufacturing Company, utilizes two photo-electric cells, sensitive to the light beam. One of the cells is a selector, which progressively chooses any one of three operating circuits when light is thrown on it. The other cell is the operator, which opens or closes the chosen circuit, thus performing the desired function.

S. M. Kintner, manager of the company’s research department, who made the demonstration, also threw music across the room on a beam of light, and light was utilized in depicting the shape and direction of stresses in mechanical materials.