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in creator/contributor: "Spellman, John M."  
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Improvement to Elevator Signal Systems

Description: Patent for an improvement to an elevator in which “to provide an elevator signal system that will permit a party at any landing to indicate his desire to go up or down to the elevator operator by pressing one of two buttons” (lines 10-15). Instructions and illustration included.
Date: February 2, 1915
Creator: Johnson, Charles S.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department

Improvement for Cotton Chopper

Description: Patent for improvement for cotton choppers “so that the operator may regulate the depth of cut, and may shift the cutting member forward or back” (lines 18-20). Instructions and illustration included.
Date: February 2, 1915
Creator: Finch, Arthur M.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department

Deep-Well Pump

Description: Patent for a deep well pump. The pump allows for existing well casing can be adapted to support the pump and valves without being removed.
Date: March 2, 1920
Creator: Ligon, Arthur Lee
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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