﻿304 Canadian Record of Science. 



long and half a mile wide. At midnight of August 

 25th-26th, during a heavy rainfall, the flood began. In 

 four liours the lake was reduced to two miles in length 

 and a quarter of a mile in breadth ; 10,000,000,000 cubic 

 feet of water were discharged, cutting down the barrier 

 390 feet ; advancing at a rate of twenty miles an hour at 

 first, and ten miles an hour further down the valley, 

 sweeping away many miles of valley road, completely 

 destroying two bridges that had been left standing, 

 because of remonstrances from local authorities against 

 their removal, and leaving no vestige of many villages 

 and three considerable towns ; yet so fully was the danger 

 announced that not a simple life was lost. 



On the Origin and Eelations of the Grenville and 

 Hastings Series in the Canadian Laurentian. 



By Frank D. Adams and Alfred E. Barlow, with Remarks by 

 R. W. Ells.i 



As the exploration of the more remote portions of the 

 great Canadian protaxis of the North American continent 

 progresses, accompanied by the detailed mapping of its 

 more accessible parts, the true character, structure and 

 origin of the Laurentian System is being gradually 

 unfolded. The work of Logan during the early years 

 of the Canadian Geological Survey, though excellent in 

 the main, is being supplemented and, in certain directions 

 corrected; and as the work is now being pushed rapidly 

 forward, it is believed that the time is not far distant 

 when, difficult as the study is, we shall possess as complete 

 a knowledge of these ancient rocks as we now do of many 

 more recent formations. In a paper which appeared 

 in 1893,^ it was demonstrated that Logan's " L^pper 



1 Published by permission of the Director of the Geological Survey of Canada. 



2 Adams, F. D. — Ueber das Norian oder Ober-Laurentian von Canada, Neues 

 Jalirbuch fiir Mineralogie. Beilage Band viii, 1893. 



