762 DARRELL H. DAVIS 



in the vicinity, however, which seemed rehable enough to be taken 

 as authority as regards the course of events, so it will be necessary 

 to imagine what actually did occur from the final results. 



The river, when first the dam broke, must have been free to flow 

 on a practically flat surface, at least not uneven enough to cause it 

 to swing from one side of the plain to the other. Neither can the 

 character of the deposits have been the cause of the meandering 

 which actually occurred. These meanders may or may not have 

 been assumed practically as soon as the dam broke and deepened 

 and made permanent since. 



The meanders developed on the withdrawal of the water from the 

 pond are not the old ones which the stream simply resumed with 

 shght deviation. The old meanders were completely obliterated by 

 silting. If this were not so, we should expect to find traces of old 

 meanders which the present stream does not occupy, but which 

 would be plainly visible as slight depressions in the valley floor. 

 These we do not find in the floor of the old pond, though they occur 

 both above and below in the valley floor. In fact, several "cut offs" 

 have had time to form in the old deposits above water at the time the 

 dam broke, farther up stream than shown on Fig. 6, but still in silt 

 laid down in the original pond. 



The old topography of the valley floor was not reproduced on the 

 withdrawal of the water due to pressing out of the water entrapped 

 in the subaqueous deposit by the increased gravity of the mass. It 

 this were so, it would be pecuhar that only one set of meanders should 

 be produced and the stream should follow them. Others would 

 show as well. The material deposited was a very fine, even clay and 

 the amount of settling which it would undergo on the withdrawal of 

 the water, from a shallow pond perhaps three or four feet deep would 

 be problematical, and perhaps of more theoretical than practical 

 importance in the determination of the course of a stream whose 

 course was determined within a few hours after the break in the dam. 



The silting up of the pond was certainly complete enough to 

 obliterate entirely the old stream courses and the settling of the mass 

 which would occur in 24 hours did not reproduce them. The new 

 meanders are independent of the old. 



The probability is, that while the water of the pond was draining 



