BULL. GEOL. SOC. AM. 



VOL. 21, 1909, PL. 34 



Figure 1. — Exd of ice-covered axd drained Rim of First Cascade of upper Rapids, 



ABOVE THE "SiSTER ISLANDS," FEBRUARY 17, 1909 (SmITH) 



Figure 2. — Whirlpool Rapids, at very low Water^ February 17, 1909 (looking 



DOWNWARD) (Smith) 



PORTIONS OF NIAGARA FALLS 



