The manner of the ice-withdrawal from the Hudson Valley, and especially its aqueous accompaniment, have long been matters of speculation and even acrimony (see subjoined bibliography). Highly divergent views persist, particularly as to the segment here discussed, yet no one has critically tested his theory by reconstructing the ancient geography step by step, as undertaken in our figures 1 to 8. The only merit claimed for these maps is that they resolve without violence a large number of facts that can not be explained satisfactorily under any other hypothesis. Their implications are considered in the sequel.
The original colored maps, exhibited by courtesy of Professor Hyde at the Cleveland meeting, were sketched in crayon on the Government topographic sheets, the ice-buried areas being first overlaid with plain paper to conceal topography and culture before the green conventions representing ice were put on—a method commended to those who desire . . .