444 OSCAR H. HERS HEY 



600 feet above the river, there are the huge fragments of a single 

 granite bowlder which had dimensions about 15 X 20 X 30 feet, 

 about 700 tons in weight. There is no gravel with them. They 

 rest on the sloping surface of the hornblende schist and appa- 

 rently were higher but have slipped down. The configuration 

 of the country is not now, and never has been, such that this 

 bowlder of Courtney granite could have rolled down from its 

 original position on the high mountain to the south. Further, 

 Salmon river never was large enough to have transported this 

 huge bowlder by any process speedy enough to have avoided 

 wearing it out. Bowlders nearly as large are now lying in the 

 bed of the river, but I have recently discovered that they rode 

 into the valley on the backs of glaciers, and the river has not 

 been able to move any of them far down stream. This bowlder 

 apparently reached about its present position by glacial action, 

 and I am compelled to refer it to the supposed glaciation repre- 

 sented by the " Channel A deposits." Aflat-lying remnant of 

 them occurs 30 feet above Cooper's flume at " Cape Horn." 



At the upper end of the gorge (at the head of Cooper's flume, 

 one and one-eighth miles up stream from Cooper's mine) we have 

 the floor of Cooper's channel (Channel C) well marked as a 

 bench on the south of the canyon, lying 75 to 100 feet above the 

 river. It is encumbered with huge granite bowlders, not much 

 decayed. Turning down stream from the head of the flume, the 

 channel bench occurs on a point overlooking the deep, narrow 

 canyon. Immediately back of it and advancing a point com- 

 pletely across it to the edge of the canyon, there is a pile of rock 

 debris rising in a steep slope to over 100 feet above the old 

 channel and then going back several hundred feet with a gently 

 rising but undulating surface. It abounds in large granite bowl- 

 ders, some of which occur on its surface. The flattened, plateau- 

 like surface sends a narrow ridge northwestward to the edge of 

 the canyon. On its southwest side there is a gently descending, 

 broad, shallow, rounded depression, clearly not the result of 

 erosion, but such a depression as commonly is found outside of 

 glacial moraines. Back of this depression there is a long, 

 smooth, gentle slope (without granite bowlders) gradually chang- 



