NORTH SYDNEY AND SYDNEY MIXES, C. B. — DkWOLFE. 293 



Sydney they strike j^, 38° E. , and are crossed by later ones 

 running N. 58° E. One mile to the west, striae run JST. 40° E. 

 The drift itself does not show by its contours the direction of 

 ice motion ; but at upper i^orth Sydney the surface is profusely 

 covered with granite boulders, whose source may have been 

 anywhere between north and southwest of this spot. 



Glacial origin must be ascribed also, in part, to Sydney 

 harbor. The upper part of Southwest Arm is deeper than tlie 

 seaward part, or than the main harbor ; and apparently shows 

 a true fjord character. The channel of this arm is from fifty- 

 four to sixty feet deep, while the main mouth of the harbor is 

 'only forty. ]^ot until one passes the mouth of the harbor and 

 reaches the open water of Spanish bay is depth found equal to 

 the deeper parts within the arm. The channel of what may 

 conveniently be called the old Sydney river, continues for four 

 or five miles out to sea, deeper than the general bottom. While 

 this may indicate only submergence of a normal river valley, 

 it may also have resulted in part from gouging, as part of 

 Southwest Arm evidently has originated. 



Throughout the field, small lakes are abundant. Sa\\Tnill, 

 or Pottle's, with an area of about five square milas, is the 

 largest. The lakes all have a longer diameter northeast and 

 southwest, parallel with the harbor front, and with the general 

 direction of the glacial striae in the district. This attitude, 

 taken with other evidence, such as the location of lakes along 

 contacts of strata, appears to point to a glacial origin. About 

 a mile east of Pottle's lake is a .small pond and bog, called 

 Ferris lake. It is connected with the former by a strip of 

 swamp about 300 feet wide, probably at an earlier time part of 

 a lake or brook bed. Ferris lake itself is in most parts but four 

 or five feet deep, and over most of its extent is merely a wet 

 bog. The whole area is about one square mile, of which water 

 occupies scarcely 300 square yards. Some of the lakes are 



