Maker: General Electric
Designer (Functional): Allen Stimson, Clement Taylor and Hans Bakke
US Patent: 2,728,265
Designer (Visual): Hans Bakke
US Design Patent: 169,721
Price (new): $49.95
Measure type: Color temperature meter
An early color temperature meter, which means it's supposed to measure the color of the light falling on it, rather than the amount, and tell you which filters to use to balance the light with the film you're using.
This is the oldest photoelectric color meter I've seen so far. My Harrison Light Corrector is older, but it's an optical meter (you look through various filters and judge for yourself). Kodak made a color meter, but that's an optical as well. My next oldest photoelectric, the Gossen Sixticolor, didn't come out until 1958.
This one is about the same size and shape as the contemporary PR-2 Guardian. The way you use it is that hold it so that the light(s) that illuminate the subject fall on the gray plastic cover (see photo). On the top edge of the meter there's a meter needle, and on the back (mouse over the photo) there's a rotating wheel (or you can turn the plastic disc--they're linked together). So you rotate the wheel until the needle lines up with the center mark. Then on the back, the window tells you which filter pack to use with your film.
To make this thing work properly, you need an insert card to drop in that matches your film characteristics (mouse-over the photo and hold the mouse button down). Since films tend to be balanced for the same few color temps, that's not such a problem. My meter came with five drop-ins: one for Kodachrome, one for Ektachrome, two Ansco Colors (one sheet film, one roll) and one "generic". I scanned them all and included them in the PDF of the instruction manual.