20 



kept steep by lateral planation. The upland is noticeably 

 uniform in height. West and southwest of Bathurst 

 on the other hand, where stronger Ordovician and Silurian 

 strata and large stocks of granite come to the surface, 

 the upland is higher and rougher. The Tertiary peneplain 

 par excellence is found along the coast of Gloucester 

 county east of Bathurst. There the upland is exceedingly 

 smooth and ow. The valleys which thoroughly indent 

 it are broad and shallow, turning and twisting in graceful 

 curves, and branching repeatedly in all directions. The 

 dissection of this part of the peneplain is fully mature. 

 Drowning appears to have taken place eaily in the Pleis- 

 tocene; at least, it is clear that before the close of the 

 Ice Age, while the interior of the province was still covered 

 by the ice sheet, these valleys were more deeply submerged 

 than now. Below the 150-foot (45 m.) level the coast 

 is very generally covered with a sheet of residual sands 

 overlying the decayed sandstones. Upon this loose 

 material rests a few inches of wave-washed sediment 

 and a scattering of subangular till pebbles and striated 

 boulders. Clearly, the weathered surface of the peneplain 

 here has escaped erosion from the continental ice sheet 

 by remaining under water while pack ice or bergs, drifting 

 along the shore, dropped glacial debris sparingly on its 

 surface. Here is true glacial "drift" in the sense used 

 by Sir Charles Lyell. The extent of this coastal sub- 

 mergence is obscurely marked by gravelly beaches which 

 range from 150 feet (45 m.) at Newcastle to 195 feet 

 (59-5 m.) at Bathurst. 



The Upland of southern New Brunswick. — Bordering 

 the Bay of Fundy coast of the province of New 

 Brunswick, is another upland distiict — the Southern 

 upland — similar in origin and in general form to the Central 

 highland. Its average altitude, however, is lower, being 

 approximately 1,000 feet (300 m.). 



Rivers of New Brunswick. — The transverse course of the 

 St. John river, from its head waters in the upland of 

 northwestern New Brunswick across the Central highlands, 

 the Carboniferous lowland and the Southern upland, to 

 the Bay of Fundy shows an extraordinary disregard for 

 structure and for recent topography. The deep intrench- 

 ment of the river through the highlands can hardly be 

 explained in any other way than by supposing that it 

 was impressed on the peneplain during the Cretaceous 



