COLBORNE TO TRENTON 355 



he gives the figures differently (386 and 436 feet above Ontario), so that 

 a line of levels was run by myself from the bay of Quinte to fix this 

 important point, the results being as follows : 



Feet 



Highest terrace (faint) 450 



Well marked terrace 441 



Rear of gravel beach 386 



Lower bar on road 374 



Rear of boulder pavement 339 



The best marked water level is the one at 386 feet, and this is the one 

 adopted by Doctor Spencer in his latest writings. His earlier estimate, 

 unless a misprint, may represent the terrace at 441 feet in the previous 

 table. The difference in level between the lowest and the highest beach 

 is 76 feet and between the two best marked water levels 55 feet, so that 

 there is an increased divergence as compared with the beaches at Silver 

 lake. 



Rounding the point of the hill, the shore runs westward ; but, owing 

 to the narrow channels between the shore and islands to the north, it is 

 hard to follow and can not be mapped with absolute certainty until a 

 contoured topographical map of the region is available. 



From the hilltop above the beaches mentioned above a number of 

 islands can be discerned to the north and northeast. 



Islands to the North and Northeast 



The shore of the bay to the north of the large island between Silver 

 lake and Trenton runs in a general way northward to Hastings, on Trent 

 river, a little below Rice lake, and an archipelago of islands of various 

 sizes — some mere drumlins, others from a mile to 7 miles long — extends 

 to the great bend southward of the Trent on its way to the bay of Quinte. 

 Twelve of these islands have been wholly or partially mapped, but some 

 were probably submerged in the earlier, highwater stages of lake Iro- 

 quois and have only the lower beaches, while one or two drumlin shoals, 

 flat topped and covered with boulders, scarcely reached the surface at 

 the lowest stage of water. 



Of these islands only a few need be treated separately. North of 

 Campbellford is a long island standing out boldly toward Crow bay, 

 just where the Trent turns south, with a steep slope from the river to a 

 series of beaches which were determined by hand level as being respect- 

 ively 432, 442, and 475 feet above lake Ontario. The work was done on 

 a rainy day, and higher beaches may have been overlooked, since Doc- 

 tor Gilbert tells me he has found beaches here or a little to the south- 

 west 90 feet apart, instead of only 43 feet. 



XLVIII— Bull. Geol. Soc. Am., Vol. 15, 1903 



