26 



group," involved, as it became, with the "Taconic" 

 controversy and the "Theory of colonies," was for many 

 years the subject of hot and world-wide discussion. Such 

 noted men as Lyell, Bigsby, Logan, Billings, Marcou, 

 Selwyn, and Hunt have repeatedly clambered over these 

 rocks, and given to the world the most diverse views as 

 to their age and relative positions. Barrande took a 

 part in the wordy war, and Lapworth furnished one of 

 the most important clues for unravelling the tangle. Al- 

 though there is still much to be learned, the discovery 

 of fossils and a closer study of the structure have elucidated 

 the main features of the region. To this more recent 

 work, Walcott, Ells, Weston, and Ami have been the 

 main contributors. 



The City of Quebec lies principally upon a narrow and 

 high promontory on the north side of the St. Lawrence. 

 To the north of the city is a broad valley, now occupied 

 by the St. Charles river, but which was, at no very ancient 

 date, the main valley of the St. Lawrence. Quebec city 

 thus occupies the eastern point of a long narrow ridge, 

 the western edge of which is at Cape Rouge, 8 miles above 

 the city. To the south of this ridge is the narrow gorge 

 now occupied by the St. Lawrence, and to the north, the 

 broad valley occupied in part by the St. Charles. North 

 and east of the latter valley is the Pre-Cambrian highland, 

 bordered by a narrow belt of Ordovician sediments. 

 South of the St. Lawrence rise the steep cliffs of Levis. 

 The sediments north of the St. Charles rest upon the 

 Pre-Cambrian, and the oldest are of Trenton (Middle 

 Ordovician) and the newest of Lorraine age (Upper 

 Ordovician). The promontory on which Quebec city is 

 built consists of shale and limestone of Middle Trenton 

 age and the strata on the south side of the river are of 

 Beekmantown age (Lower Ordovician). 



The prevailing strike of all the beds is northeast-south- 

 west, magnetic, and the strata are thrown into tightly 

 folded, overturned anticlines and synclines with steep 

 dips to the southeast. There are three major faults 

 approximately parallel to the strike, two of them thrust 

 faults with a heavy throw to the northwest, and one 

 normal fault with a drop to the southeast. The first 

 of the thrust faults occupies the bed of the St. Lawrence 



