Near the close of the last century the region around the mouth of Lake Chelan was visited by several of the early reconnaissance parties.2 Somewhat diverse interpretations of the glacial features, particularly of the broad terrace that hangs 600 feet above the Columbia, were proposed and the region became the subject of considerable controversy.3 It was the writer’s good fortune to spend most of the summer of 1931 in a portion of the Columbia Valley where the physiographic features associated with the advance and recession of the last ice sheet are well displayed. Although the investigation was primarily of petrologic character, it is believed that sufficient data regarding the glaciation of the district were gathered to be worthy of record, and that the observations here presented will be of assistance in evaluating some of the controversial interpretations.
Eliot Blackwelder has kindly read and offered suggestions regarding the manuscript, and . . .