The river occupies a narrow rock gorge for a mile north of the bridge, but at that point the valley widens out. This entire section of the river’s course was established on the old bed of glacial Lake Hadley; but after the unconsolidated deposits were washed away, the stream found itself flowing along the weak contact between the Triassic conglomerate on the west bank and the metamorphic rocks of the highlands on the east bank. The river deepened its channel on the weak contact zone and made the scenic cut over which the bridge was built. The pre-glacial valley lies beneath the sand plain east of the river. Millers River crosses this old valley between Millers Falls and its confluence with the Connecticut, at the east end of the bridge. The rapids at the junction can be traced to the ridge of crystalline rock between the east bank of the present Connecticut and the west bank of the pre-glacial Connecticut. The resistant ledge forms a barrier which Millers River has not yet eroded to its grade. The conglomerate beds on the west wall of the gorge dip steeply eastward towards the river and end against the crystallines. The beds were originally laid down with a gentle westward inclination. They were tilted steeply in the opposite direction against the crystallines by faulting, which elevated the ranges and pressed down the adjacent basin during Triassic time. _Titan’s Piazza and Titan’s Pier_ Not so long ago, giants and the devil received the credit or the blame for such oddities in nature as rock-masses broken into six-sided columns. Ireland has its Giant’s Causeway, and Yellowstone National Park its Devil’s Post-pile. Titan’s Piazza and Titan’s Pier were likewise attributed to activities of the leader of fallen angels and were given names appropriate to such an origin by the early settlers. Dr. Hitchcock, in characteristic fashion, undertook the task of correcting the errors of puritanical psychology by renaming these places during one of the early Mountain Day trips from Amherst College. The entire college body sojourned to the west end of the Holyoke Range to hear the cliffs renamed and their true nature explained.