Page:The Selkirk mountains (1912).djvu/154

136 CHAPTER V.

THE DOGTOOTH MOUNTAINS.

From a sketch by A. O. Wheeler.

The geography of the Dogtooth Mountains is doubtful. As yet they do not appear to have been definitely assigned to any of the established mountain systems, but seem to be an outlying group by themselves. On his Reconnaissance Map of "a portion of the Rocky Mountains" published in 1888, Dr. Dawson embodies them in the Selkirk Range. But the latest Dominion Government maps do not use the word. "range" in connection with the Selkirks. According to such maps the Selkirk Mountains occupy the entire country enclosed by the great loops of the Columbia and Kootenay Rivers; while the Dogtooth Mountains, Spillimachen Mountains, and Shuswap Mountains are minor groups of the same system.

The north-eastern boundary of the Selkirk Mountains is the deep and wide Columbia-Kootenay trough or "Great Rocky Mountain Trench" within which the Columbia flows north-westerly, and the Kootenay south-easterly. The greatest elevation of the trench above sea-level is at Canal Flats at the head of Columbia Lake—2,740 feet. Almost through the centre of the Selkirk Mountains a similar trench has been cut, consisting of the long, narrow valleys of Flat Bow or Kootenay Lake, Howser River and Lake, the Duncan River flowing southward and the Beaver River flowing northward. The highest part of this trench is at the divide between the two streams last named—4,600 feet above sea-level. This less deeply cut and narrower trough joins the great Columbia trough close to Beavermouth Station on the Canadian Pacific Railway. In an article on the subject published in the Geographical Journal (Vol. 27, p. 600), Dr. Reginald Daly has named it the Purcell Trench and would thereby seem to indicate that all enclosed by it and the Columbia-Kootenay Trench is part of the Purcell Range. On Palliser's map of "Explorations in the Rockies from 1857-1860" the Purcell Range is shown occupying but an insignificant part of this area. On the same map the Selkirk Mountains are shown to occupy only the upper half of the area enclosed by the Columbia and Kootenay Rivers.

Now, there are no maps earlier than Palliser's until you get back to Thompson's (1812), and Dawson appears to have followed his (Palliser's) nomenclature. Little change had been made since Dawson's map of 1886 until Dr. Daly introduced the appellation. Purcell Trench, which naturally extended the area of the Purcell Range. It seems to fill a want and to dispose of a somewhat complicated geography.

Their geological structure distinctly separates the Selkirks from the Rockies, so that it is reasonable to define the Selkirk Mountains as bounded by the loops of the Columbia and Kootenay Rivers, and the Purcell Range as a subdivision, bounded by the ColumbiaKootenay and Purcell Trenches. This places the Dogtooth, Spillimacheen and Shuswap Moimtains as minor groups of the Purcell Range, the first-named being situated at its northern extremity. Defined by limits, the Dogtooth Mountains are bounded on the north and east by the Columbia River, on the south and west by the north