[POOLE] PRE-GLACIAL RIVER OF GULF OF ST. LAWRENCE 145 



occupied by Carboniferous Limestone and later deposits. The fork in 

 the main channel marking the junction of the Margaree river, is fol- 

 lowed upstream by a broad interval many miles in length. While much 

 of the surface smoothed over by the later deposits presents but gentle 

 undulations, there are parts more elevated, suggestive of low hills in 

 range with the general shore line, and in other places the contours 

 crowd together, indicative of steep, if not precipitous banks. The 

 soundings record but few exposed rocks and no jagged peaks, remnants 

 of older formations projecting through the Carboniferous strata, no 

 marked break or sharp deflections that would suggest changed condi- 

 tions along the general course of the main stream, but rather a con- 

 tinuation of the river flowing in measures no older than the Carbonifer- 

 ous Limestone. 



This river system gathered the waters of western Cape Breton, of 

 the counties of Pictou and Antigonish, and of eastern and northern 

 Prince Edward Island. It also carried off half the drainage of a large 

 irland now represented by the group of the Magdalen. The fountain 

 head of this pregiacial stream would be that of the Pictou rivers, giv- 

 ing it a total length of some 200 miles. An important branch joined 

 the main stream from the westward flowing between the Magdalen and 

 Prince Edward Island at a depth below the present shore line of 240 

 feet. But the sea currents and the glacial drift have obscured the 

 structure of this part of the gulf more than on the courses of the main 

 stream. 



iSTothing is shown on the map of the ancient drainage of George 

 Bay and its connection with the Strait of Canso, the course also of a 

 contemporary pregiacial river. 



Shoal ground lying between Port Hood and Cape George marks a 

 connection of the old rock range of the Cobequid, through Pictou and 

 Antigonish counties across the bay, with the continuation through 

 Inverness county. Doubtless there were channels on the faulting that 

 changed the direction of the range and influenced the sub-aerial ero- 

 sion, but no conclusion was reached as to the direction of the flow into 

 or from George Bay. 



With the location of the affluents of the submerged river, the story 

 it has to tell is not ended. It bears the stamp of family lineaments, of 

 parent streams that irrigated the same fields in previous cycles. How 

 many there were has not been made out, nor the relation borne by the 

 river to the important epoch when the deposition of the thick workable 

 coal seams marked a period of subsidence. But it does seem as though 

 there were some relation between the patches of Coal Measures bearing 

 workable coal fields and the area confined between the old rocks of the 



