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ROYAL SOCIETY OF CANADA 



taken up there was no set purpose to find a departed river or to develop 

 such a structure as the map shows. There was no expectation of such 

 a result being reached, but as order and plan seemed to grow under the 

 pencil and eraser, the work developed into system as represented. 

 Through paucity of information, infrequent soundings in many parts, 

 some minor license required to be exercised to supply the want of 

 detail, and in such places, fewer brooks and branches to the river are 

 shown than must have existed. 



The method pursued in working out the structure was by running 

 contour lines in the manner ordinarily adopted in plotting land sur- 

 veys, and which actual observation has justified. When so treated, the 



çr \ n c e 





undersea floor was found to take on a structure with depressions metho- 

 dically arranged, decreasing in depth as distance landward increased 

 from the edge of the plateau taken at 100 fathoms. Then connecting 

 the embayments along these contours by lines of shortest distance, a 

 system of drainage stood revealed along continuously descending 

 grades, such as would be occupied by flowing streams over a similar land 

 surface. 



There are certain features of the submerged river courses that 

 may be of sufficient interest to note. There is the greater proximity of 

 the river to the present shore line where the coast is bolder and the 

 oldest and hardest rocks touch the sea, determining in the early stages 

 CÎ the previous cycle the direction of the drainage parallel to the hill 

 I anges. This parallel feature is also noticeable in the* mounds, once 

 islands, which, indicated by the contours under water, likewise suggest 

 a continuation seaward of the geological structure of the coast terrace 



