346 ASSINNIBOINE AND SASKATCHEWAN" EXPEDITION. 



the drifting sands of the south-west, like those of the north, 

 appear to be "derived from the sandstones of the Tertiary 

 period. 



In the Upper Saskatchewan, Tertiaries containing Coal 

 or Lignite are well developed ; also on the flanks of the 

 Bocky Mountains. They are mentioned in the following 

 notices of the Lignites of the north-west. 



TERTIARY COAL, OR LIGNITE. 



Although the Lignites are not generally available for 

 economic purposes, yet some seams sufficiently pure for 

 use are known to exist in the great Lignite basin of the 

 Upper Missouri and Saskatchewan. A brief notice of the 

 character of this important material as it occurs in the 

 Tertiary rocks of the North- West, will enable a tolerably 

 accurate judgment to be formed of its probable value as a 

 source of fuel in Eupert's Land. 



The great Lignite Basin of the Missouri extends from 

 the 100th to the 108th degree of west longitude, and from 

 the 45th degree of north latitude to an unclescribed limit, 

 probably through the Valley of the Saskatchewan to the 

 Valley of the Mackenzie. 



Dr. Hayden, who traced the great Missouri formation 

 up that river for a distance of 600 miles, and up 

 the Yellowstone for 300 miles, considers that the fossils 

 obtained from it show conclusively, that it possesses 

 the mixed character of a fresh water and estuary de- 

 posit, and that it cannot be older than the Miocene 

 period. It is composed of clays, sands, sandstones, and 

 Lignites. The extent of country known to be occupied 

 by this basin, as it occurs on the Missouri and its tribu- 

 taries, exceeds 60,000 miles. The beds of Lignite in this 



