BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 
VOL. 9, PP. 101-110 : JANUARY 25, 1898 
NIAGARA GORGE AND SAINT DAVIDS CHANNEL 
BY WARREN UPHAM 
(Read before the Society December 30, 1897) 
CONTENTS 
; Page 
TARO SIOCTHOM, ‘0 5.5 ¢ Bo hea OIA CRG ea RICE SDI CER eR CIEE caren ae 101 
NIGGA, GORA. <0 's.b gars Makes eerste CEO CeIn RES eek OOo ete 102 
insicaleteaturessimgenerall 22.4... ccs sone ae Gaels eblag sue sao) ewes 102 
Hrommelewistoneto the swWilinlpoolwses co acdeccce csc asee occas aes: ee cee lee 103 
BINION VALE LO OO lever gevscisiersaseeescepmintas cull ore icy yh: Ne cheers Moe sienet nea alm Saat uae hs ... 104 
PinewVVAnTlpOOlsTA PIAS 45 valerie oes ek Si ate cialis as imieyeis este sw isauece dae mies 104 
From the rapids to the falls................... CS Rae ae UREN NOIR i EL sp 104 
Srint; DANG Cotas) Boman ee one ue acme cea rec caaec ea Ent amie eA Sov ayes 104 
From Saint Davids to the Whirlpool...................... oe coher ae, 104 
Probable preglacial extent above the Whirlpool......................... 105 
itectronmbuaemecession of the) fallsis. 5... sneaenasucar s+ aces sees ct edeee. 106 
Effect of the Laurentian glacial lakes on the Niagara Gorge erosion ......... 1107 
Gilacialelakesiabove: Niagara TiVer «0... arassee se aeessssessr esses ns 107 
Gilaeiallakesihelow Niagara river... o...¢.5.-. sce. eee tee ent eee canes 108 
Epeirogenic uplifting contemporaneous with the glacial lakes................ 108 
Epeirogenic movement continued to the present time.......... ............ 109 
Duration of Niagara falls and the Postglacial period...................-..-.. 109 
INTRODUCTION 
Having recently again examined the Niagara falls and gorge with 
especial reference to the older channel of Saint Davids, I believe that a 
most important element in the history of the gorge erosion has been over- 
looked by some observers, and that by others its evidences have been 
misunderstood. This papershows that the small preglacial stream which 
eroded the Saint Davids and Whirlpool channel, having a great depth 
beneath the river in the Whirlpool, must have flowed for a considerable 
distance, before reaching that depth,in a gradually widening and deepen- 
ing ravine, coinciding with the present gorge along the Whirlpool rapids. 
Because the Niagara river found there a drift-filled narrow ravine, which 
it cut to the present size of the gorge, its ergsion took place in that part 
by rapidsand cascades. Southward from the head of the old ravine the 
river has eroded its gorge by a great vertical cataract, under which the 
XV—Butn. Geox. Soc. Am., Vou. 9, 1897 (101) 
