594 DEPARTMENT OF THE INTERIOR 



2 GEORGE V., A. 1912 



were at their maximum thickness many of the high spurs were submerged. 

 Many erratics from the Castle Peak granite stock were observed at the 6,850- 

 foot contour on the ridges of the north, indicating a local streaming of the ice 

 toward the Belt of Interior Plateaus in British Columbia. Other erratics from 

 the same source are sprinkled over the Hozomeen ridge to at least the 6,200-foot 

 contour, showing again clearly that a heavy, broad stream of ice from Castle 

 Peak moved across the deep canyon of Lightning creek and became confluent 

 with the main glacier flowing down the Skagit valley. As the climatic con- 

 ditions changed, the ice-currents became more localized in the valleys, but the 

 erosive work, including the formation of cirques and the sharpening of the 

 ridges by head-wall recession, continued long after the maximum glaciation was 

 passed. As a result the Hozomeen range i3 one of the most rugged of those 

 crossed by the Forty-ninth Parallel. 



We have seen that the upper Glacial limit of the ice-cap on the west side 

 of the Okanagan range was 500 or 600 feet lower than the upper limit in the 

 eastern half of that range. It is also quite clear in the field that the Hozomeen, 

 as well as the Skagit ranges were not covered by such continuous ice-caps as 

 were the ranges farther east. Yet we must not conclude that the precipitation 

 of snow was any less in the former ranges. The probabilities are rather in 

 favour of the view that the Hozomeen and Skagit ranges received a somewhat 

 higher annual proportion of snow than the Interior Plateaus, the Columbia 

 mountain system, or the Selkirk mountain system. The local character of 

 the glaciation in the Hozomeen range, as in the Skagit range, was rather due 

 to the fact that the pre-Glacial canyons were there deeper than those of the 

 eastern ranges, and the valley gradients were steeper. Prom the opening of the 

 Glacial period the outflow of ice toward the sea or toward the unglaciated tracts 

 must have been much faster in the western ranges. Their local glaciers, by 

 rapidly deepening the canyon, must have attained still greater ability to drain 

 the snow-fields and so lower the average level of the ice. East of the Okanagan 

 range, for 300 miles, the Cordillera was flooded in ice, the fairly even surface of 

 which was broken by a few nunataks, like islands in a vast lake. West of that 

 range a general flood was impossible, since the pre-Glacial topography offered 

 many deep channels along which the ice was, with relatively high speed, 

 drained away. 



Of these effluent channels the Skagit valley was the master for the 

 Hozomeen range and for the eastern slope of the Skagit range. Through that 

 wide and deep trough an enormous stream of ice moved down, to swell the 

 piedmont sheet in Admiralty Inlet. 



Skagit Eange. 



Though the Skagit range did not bear a continuous ice-cap in the 

 Pleistocene period the effects of powerful glaciation are manifest 

 wherever the range has been explored. With the possible exception of the 

 Clarke range, no other part of the Cordillera on the Porty-ninth Parallel can 



