An undated aerial view of the Short Mountain Colliery of the Lykens Valley Coal Company, Bear Gap, Dauphin County, Pennsylvania, showing rail tracks and some colliery coal cars on a siding (at right) near one of the boiler houses. Another boiler house is seen at the left side, with four chimneys rising from it. Until 1921, when the electrical plant was completed, the entire colliery ran on steam which required the use of good coal, which ate up some of the possible profits that could have been made on open market sale of the coal. The building near the center is a tool shed.
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