72 



Maria and O'Connor streets, some 12 feet below the surface of the road-^ 

 way. At these two places, whilst the shales of the Utica fomnation 

 also occur in situ and undisturbed at a greater depth than is visible in 

 either section, the "Uppermost measures of the section exposed and 

 exan)ined cannot certainly be said to be strictly in situ, as the beds are 

 tilted at every conceivable angle, crushed and broken, and in the over- 

 lying glacial deposits are to be found some of the boulders themselves 

 which assisted intilting and disturbing these once horizontal measures- 

 There occur a vast number of faults and dislocations in the measures 

 of the Trenton and other formations about Ottawa, great breaks, which 

 at times, run more or less parallel to each other and were the result of 

 great pressure brought to bear upon the beds in question. Whether 

 these faults and breaks are due to disturbances which took place about, 

 the close of the Silurian Age, or at the introduction of the Devonian, 

 when Rigaud and Montreal mountains, and other similar volcanic or 

 intrusive masses, were ejected amidst great perturbation ; or whether 

 some of these faults were not in part due to the enormous pressure which 

 the great ice-mass exerted upon the strata in later glacial times arc 

 questions which, though readily suggested to one's min(7 by the- 

 phenomena examined, do not find so ready a solution. Having now 

 examined the number, direction, movements, thickness and the e)-osive 

 power of the glaciers during this Great Ice Age, having very cursorily 

 glanced at the results which were eflfected in giving to the country the 

 general appearance which it possesses at the present day, there remains 



to find out what are the materials and under what conditions they were 

 deposited. 



The masses of boulders, also termed " boulder clay," " moraine- 

 profonde,'' &c., unlike both the underlying older and overlying newer 

 deposits are not stratified, i. e. they have no divisional planes of strati- 

 fication or true bedding. Pebbles of various sizes and of every kind of 

 rock in the district, usually rounded and smooth, held together or 

 cemented by an argillaceous paste or clay with a certain admixture of 

 arenaceous material derived from the more finely crushed detritus and 

 debris at the bottom of the glacier, form the lowest division of our 

 Post-Tertiary deposits. These " boulder clays," as they are appro- 

 priately terBied, have a very large percentage of boulders in them, the 



