National Geographic : 1943 May
4'. Three "Mountain Climbers" Struggling Like Ants up the Shifting Side Indicate the Colossal Size ofThis Man-made "Chat" Dune Chat is the word for waste discarded from lead and zinc mills. The bulk in this heap in southeast Missouri would layaroad, estimated at30feet wide and one foot deep, from coast to coast. Chat is used for Missouri roads and for railroad ballast (page 590).