SOME LOCAL DETAILS. 187 



about one hundred and fifty feet above the level of the 

 sea, and is composed of clay, capped with sand and gravel. 

 At no great distance inland, there rises a second terrace 

 one hundred and sixty feet higher than the first, or about 

 three hundred and ten feet above the sea. In some 

 places the front of this terrace is cut into two or more. 

 It consists of clay capped with sand and gravel, with some 

 large stones and Lauren tian boulders. Still farther inland 

 is a third terrace, the height of which was estimated at 

 four hundred to four hundred and fifty feet. 



In the first mentioned of the above terraces, a very 

 deep railway catting has been made, exposing a thick bed 

 of homogeneous clay of a purplish gray colour, and 

 extremely tenacious. It contains few fossils ; and these, 

 as far as I could ascertain, exclusively Leda glacialis. It 

 is, in short, a typical Leda clay, and its thickness in this 

 lower terrace can scarcely be less than one hundred and 

 twenty feet. As the inland terraces are probably also 

 cut out of it, this may be less than half of its maximum 

 depth. Under the Leda clay a typical boulder-clay had 

 been exposed at one place in digging a mill sluice. It 

 seemed to be about twenty feet thick, and rests on the 

 smoothed edges of the shales of the Quebec group. 



Though the Leda clay at the Trois Pistoles seems 

 perfectly homogeneous, it shows indications of stratifica- 

 tion, and holds a few large Laurentian boulders, which 

 become more numerous in tracing it to the westward. A 

 short distance westward of Trois Pistoles, it is seen to be 

 overlaid by a boulder-deposit, in some places consisting of 

 large loose boulders, in others approaching to the character 

 of a true boulder-clay or associated with stratified sand 

 and gravel. We thus have boulder-clay below, next 

 Leda clay, and above this a second boulder-drift associated 



