200 THH ICK A(;H in CANADA. 



ill ail cli'Viitidii (if iiltdut ;"(»() feci .iIkivc the sea. Kaurcn- 

 liaii Itouldcrs, probably diiftcil on ice iu the laler glacial 

 au'c, jire fdund at a still iiiuher level. 



The site of the Tetei' liedpath Museum present.s 

 another interesting example of the si)ecial features of the 

 drift-deposits on thi' soulli side of ^Montreal mountain. 

 Tiie first floor of the museum is 100 feet above the level 

 of the sea, which is about the height to which intense 

 glacial ion and boulder-clay extend on the mounlain,* the 

 terraces above this level l»cing of sand and gi'avel, and 

 the limestone and trap of the nKJuntain weathered and 

 deeply deconi'posed and not covered with the boulder-clay. 

 Thus the foundations of the building were excavated into 

 a slope at the exact junction of the glaciated and non- 

 glaciated surface. The excavation for the front of the 

 building was made iu louu'h boulder-clav, with large 

 Laurentian and limestone boulders, and this rested on an 

 intensely glaciated rock surface of limestone, with striae 

 bearing S. '.]:] W. The rear of the building was cut into 

 the same limestone, not glaciated, and decomposed to a 

 depth of 20 feet or more into an earthy, crumbling 

 mass, still showing the stratitication and fossils of the 

 formation. 



There could not be a finer illustration of the "ice-foot" 

 of the margin of the old Pleistocene sea ; and any idea 

 of glacier action was excluded by the directions of the 

 striae, and by the absence of any lateral moraine. 



The most strongly marked terraces on the ^[ontreal 

 mountain are at heights of 470, 440, 'AHij, and 220 feet 

 above the sea, but there are less important intermediate 



* The heavy ghioiatiou on the phiteau north-east of tlie mountain 

 e.xtenila up to about 180 feet. 



