National Geographic : 1923 Apr
ODiggins Airial Photo Co. AN AIRPLANE VIEW OF THE CLEARING EAST CLASSIFICATION YARD, NEAR CHICAGO This picture shows the layout of a modern classification yard. Two trains to be "broken up" and their cars made upinto other trains may beseen in the foreground. The "hump" (see text, page 391) is on the near side of the little house spanning thetracks intheforeground, and theslope runs down into the yard. Up in this bridge house are men who operate electrically controlled switches. They press agiven button, thecorresponding switch is set, and the cars intended for the train being made up on the track which this switch opensare uncoupled and allowed toroll bygravity to their appointed position. Clearing Yard, as a whole, is five miles long, contains I80 miles of track and 799 switches, and canhandle 10,000 cars aday.