Tungsten& Counterweights in tanks

In combination, a counterweight assembly for theatrical scenery comprising a hollow tank supported for guided vertical shifting, flexible scenery suspension lines having one set of ends thereof anchored to said assembly, elevated antifriction guide means over which mid-portions of said lines are passed with said tank comprising a counterweight for scenery to be suspended from the other set of ends of said lines, said tank including liquid inlet and outlet means, and liquid supply means and liquid drain means operatively connected to said liquid inlet and outlet means for selectively pumping liquid into and draining liquid from said tank, a support or purchase line and vertically spaced rope guide means about which said support line is trained to define a pair of upstanding reaches extending between said rope guide means, said tank being interposed in and supported from one of said rope reaches.

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