National Geographic : 1926 Jul
THE NATIONAL GEOGRAPHIC MAGAZINE S 80 78 76 74 Drawn by C. E. Riddiford THE FRONT-LINE TRENCHES OF THE RIVERS OF NEW YORK The dotted lines show the areas drained by the master rivers of the Empire State, most of which have driven spearheads into the terrain of their rivals. It is particularly interesting to note how the east fork of the Susquehanna has driven its way northward to the very ramparts of the Mohawk at Little Falls. Photograph by A. C. Spencer THE BIRTH OF AN ALASKAN GLACIAL STREAM Many a furrow that later formed the bed of a stream has been plowed by glacial ice. Likewise it has driven many a river into the lap of a rival watercourse (see text, page 117).