6 9 



(14 m.) to the whirlpool. Careful estimates indicate 

 a depth of 35 to 40 feet (10 -6 to 12-2 m.) in the lower 

 part of the rapids, but Spencer's soundings indicate nearly 

 twice this depth under the upper railroad bridge. 



South of the railroad bridges the electric railway 

 begins the ascent to the top of the Upper Great gorge. 

 This climb affords magnificent views of the northern 

 part of this section and of the place where it suddenly 

 contracts and the narrower gorge of the Whirpool rapids 

 begins. As the car climbs the wall of the gorge good 

 exposures of the Clinton limestone, the Rochester shale 

 and the Lockport limestone are obtained. Just after 

 passing under the steam railway the surface of the lime- 

 stone shows glacial polishing and scratching. 



NIAGARA FALLS TO HAMILTON. 



From the station on the Canadian side the train 

 proceeds by the Grand Trunk railway to Hamilton. 

 About a mile north of Niagara Falls, Ontario, the railway 

 passes within a quarter of a mile of the western cliffs 

 of the whirlpool and farther north crosses two or three 

 sharp ravines of the headward streams of Bowman creek. 

 Beyond this the view discloses no evidence of the buried 

 St. David gorge. Instead, one sees to the east a level 

 plain and fertile fields. At the head of the embayment 

 south of St. David there is a great deposit of gravel which 

 has been extensively excavated for ballast. These gravels 

 are of glacio-fluvial origin and were deposited in connection 

 with one of the slender moraines which crosses this region. 

 In passing the gravel pits the cross bedding of the deposits 

 may be seen from the train. 



As it passes through the gravels the railway turns to 

 the west and begins a long descent down the face of the 

 escarpment. In a cut about a mile and a half (2-4 km.) 

 west of the pits a few exposures of Lockport limestone 

 may be seen and, about a mile farther on, the Rochester 

 shale. Half a mile west of this and about a mile east 

 of the Welland canal there is a fairly level terrace formed 

 by the Whirlpool sandstone, but only small exposures 

 of the rock are seen. Welland canal which is crossed 

 next, is one of the largest and busiest canals on this con- 

 tinent. Continuing, the railway descends gradually to 

 the flat clay plain below the Niagara escarpment. At 



