My IA buddy Rolf Lee of San Francisco tells me that board's inventor was George Van Buren, also out of Local 16. The brochure:
The 1957 version of the Davis Dimmer "Consolette" I operated in summer stock at Highlands, NC. Davis Boards had six slider dimmers, each rated at 2.4K, but the overall coil capacity was 12K, not to be exceeded. There was no mastering, except for a Blackout Switch (main breaker). Each color-coded slider connected to an A and B switch, allowing fast patching between two different circuits.
The inventor, Ariel Davis (1912-1997) was an innovator who also introduced aluminum-body lighting instruments, including the first Par Can. As opposed to the wall-mounted boards of the era, one could see over the controls of a Davis Dimmer, and he encouraged theatres to install them Front-of-House, another innovation.
Ariel Davis' larger boards employed Superior Luxtrol dimmers as proportional masters, but the largest Luxtrol was 6K, half the capacity of the sliders.
Despite being manufactured in Salt Lake, Davis Dimmers were favored by Nuns.
I believe this to be "Unto these Hills" in Cherokee, NC, but I may be wrong.
Ward-Leonard manufactured and supplied most of the resistance dimmer plates ever installed, supplying both Hub and Frank Adam, the two major competitors, as well as Westinghouse, GE, Trumbull, Kliegl, and Century. Behold their 1937 Bulletin, courtesy John Chappell: