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��lowest prairie-level, and lies along the base of the eastern LaurenCian plateau, has an altitude of about eight buticlrcd feet only. From this level, with minor exceptions, the snrrace may be regarded as sloping gradually and continu- ously upward, at a rate of from four to five feet in the mile, to the foot-hills. There the hori- zontal and unaltered strata of the cretaceous and Laramie formalions break against the base of the ancient rocks of the mountains into a series of sharp and nearly parallel flexures, producing a varied and picturesque region, with quite peculiar characters. In the central portiou of the plains, the most marked excep- tions to their generally even and monotonous contour are found in the tumultuously hilty belt of country known as the Missouri Coteau and in a line of diffuse and indefinite elevations nearly parallel to the Cflteau, which inulndes Turtle Mountain, Moose Mountain, and the File and Touchwood Hills. Tbese hills, or mountains so called, are really tracts of con- siderable size, with rolling or hilly surface, more or less wooded. The northern extension of the C'lteau, where known as the Eagle Hills, near Baltleford, also becomes partly wooded.

To any one familiar with the territory lying west of the Missouri, the most remarkable dif- ference of a general character, observable in this northern extension of the same region, is perhaps the extraordinary abundance of small lakes, ponds, or ' sloughs,' which are scattered everywhere over its surface. This peculiarity is evidently in connection with the mantle of glacial drift, which is here universal, and (iependent on the irregular deposition of its material. The lakes and ponds, while at times arranged in intercommunicating linear series, are usually distributed without the least ap- parent regularity, and occupy shallow basins without outlet. Filled by the melting of the snow or rains of the early summer, a great pro- portion are completely emptied by evaporation before the autumn, while the water remaining in others becomes more or less distinctly saline in many instances. This is more particularly the case with those of the southern and more arid portion of the region. Near the northern margin of the plains, siilinc lakes are quite ex- ceptional. It is generally on the edge of one of these rush-bordered pools that the traveller makes his evening camp ; and, while the abun- dance of water in one respect facilitates travel in the spring and early summer, the moist con- dition of the deep alluvial soil at these seasons may prove a more than countervailing dis- advantage. The most serious obstacles, how-

��ever, to be met within longjournevs across the plains, are the various rivers. The Assiniboine, Souris, Qu'Appelle, and other streams of the eaetcrn district, during the breaking-up of the ice, and for some time subsequently, may prove formidable barriers in the absence of bridges or ferries. The North and South Saskatche- wan, the Red Deer, Bow, and Belly rivers, all eventually uniting to pour their waters into the northern end of Lake Winnipeg, rise far back in the Rocky Mountains, and, while subject to considerable spring freshets in some seasons, are generally not in full flood till June or July, when the snow is disappearing from the highest summits of the range, and the snow-Qelds and glaciers alwut the sources of some of them are melting most rapidly. These streams have trenched valleys across the surface of the plains, which are generally from a hundred to three hundred feet in depth, and a mile to two miles or more in width. All the trails used as regular means of communication make for recognized crossing- pi aces on these rivers, where the approaches are favorable, and where very generally the river may be fonled at low water, though ferries of some kind have usually of late years been established for use at other seasons.

As above indicated, almost all the larger river-valleys hold more or less timber; and in the northern part of the region this is not con- fined to the bottom-land, groves and thickets spreading also into the lateral valleys ('cou- lees ') and broken ground which is very gener- ally to be found in the vicinity of these great river- troughs. .Should any serious ojiposition be offered to the expeditions now on their way to quell the present unfortunate disturbance, it will in all probability be at one or other of the ' crossings ' which naturally lend them- selves to defence. The rivers, as might be expected from the considerable general inclina- tion of the surface, are usually rapid and shal- low, with numerous gravel-bars, and reefs of bowlders, at low water. They are often, more- over, extremely tortuous ; and in consequence of these peculiarities, and the considerable por- tion of each year during which they are ice- bound, they are not extensively utilized as means of communication ; and trains of wag- ons or Red-River carts are still generally cm- ployed in travelling, or in the transport of sup- plies and goods at a distance from the railways. The Hudson-Bay company has, however, for a number of years, used a couple of small stern- wheel steamers between the Grand Rapids, near Lake Winnipeg, and Edmonton, far up on the North Saskatchewan. Two or more steamers

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