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While setting up retainers, the eastbound Chief comes through Summit. In the picture below, you can see the station. The short track on the right was used while cutting out the helper on eastbound trains. The helper would shove the caboose into this short steep spur. After uncoupling and moving out of the way, the brakeman on the caboose would kick off the hand brake and the caboose would roll off the little hill and re-couple to its train. The helper would then turn on the wye and return to San Bernardino.