REPORT OF THE CHIEF ASTRONOMER 41 



SESSIONAL PAPER No. 25a 



Dawson did not fix a southern limit for the Coast range. General usage 

 has not fixed the northern limit of the Cascade range. The solution of the 

 problem is obvious if the principle of limiting units by master valleys and 

 trenches be applied. The Fraser river valley clearly supplies the required 

 boundary between the two ranges. There seems to be no other simple adjust- 

 ment of the two usages, which undoubtedly sprang up because of the existence 

 of a political boundary at the Forty-ninth Parallel. It is important to note 

 that the delimitation here advocated is not new, since it appears on two of the 

 earliest official maps of British Columbia — those accompanying the 1859 

 British Blue Books, entitled ' Papers relative to the affairs of British Columbia.' 

 The remaining boundaries of the Cascade and Coast ranges, as well as the 

 boundaries of the Olympics and of the Vancouver range, are at once derived 

 from the map, and need no verbal description. These natural boundaries seem 

 in large part to be located along structural depressions, and belong, therefore, 

 to a type unusual in the Canadian Cordillera. 



The subdivision of the system where it crosses the Forty-ninth Parallel 

 has already been recognized by Bauerman and, more in detail, by Smith and 

 Calkins.* With these authors the present writer is in accord on the matter 

 and a quotation from the report of Smith and Calkins will suffice to indicate 

 such subdivision as seems necessary for the present report. 



1 In northern Washington, where the Cascade mountains are so prom- 

 inently developed, the range is apparently a complex one and should be 

 subdivided. This was recognized by Gibbs, who described the range as 

 forking and the main portion or ' true Cascades ' crossing the Skagit where 

 that river turns west, while the ' eastern Cascades ' lie to the east. Bauer- 

 man, geologist to the British commission, recognized three divisions, and 

 as his subdivision is evidently based upon the general features of the relief 

 it will be adopted here. To the eastern portion of the Cascades, extending 

 from mount Chopaka to the valley of Pasayten river, the name of Okanagan 

 mountains is given, following Bauerman. To the middle portion, includ- 

 ing the main divide between the Pasayten, which belongs to the Columbia 

 drainage, and the Skagit, which flows into Puget sound, Bauerman gave 

 the name Hozomeen range, taken from the high peak near the boundary. 

 For the western division the name Skagit mountains is proposed, from the 

 river which drains a large portion of this mountain mass, and also cuts 

 across its southern continuation. It will be noted that the north-south 

 valleys of the Pasayten and the Skagit form the division lines between these 

 three subranges, which farther south coalesce somewhat so as to make 

 subdivision les3 necessary. 



1 The Okanagan mountains form the divide between the streams flow- 

 ing north into the Similkameen and thence into the Okanagan and those 

 flowing south into the Methow drainage. In detail this divide is exceedingly 

 irregular, but the range has a general northeast-southwest trend, joining 



*G. 0. Smith and F. C. Calkins, Bull. 235, U. S. Geol. Survey, 1904, p. 14. 



