Bruckner-Mitchell was a stage rigging house in New York City from 1928 until 1940, according to trade magazine listings, and the lead was Richard R. Bruckner. Bruckner had worked for Peter Clark as an engineer, according to an article from 1925, and in 1931 he was granted a patent for a traveler track. If Peter Clark had published a catalog, it would look a lot like this, and in fact many of the devices illustrated herein (arbors, counterweights) look exactly like those of Peter Clark. No further information about the firm could be found.
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