« 이전계속 »
CHAPTER I I.
Physical Geography of Manitoba.
Its Situation and Boundaries— Area-General Characteristics-Red River PrairiePembina Mountain-Wet Country along its Base—Riding Mountain—View from its Summit-Dauphin Lake-Duck Mountain-Lake Winnipeg-Lakes Manitoba and Winnipegoosis-South Western Manitoba—Turtle Mountain-Red River-Graphic Picture of the Prairie near Winnipeg-Fort Garry-Assiniboine River-Land on Assiniboine--Souris River-Snake Creek-Oak Lake – Vicinity Suited for Stockfarming-Sand Hills, at Snake Creek-Little Saskatchewan-Land on Little Saskatchewan-Settlements in its Valley-Shoal Lake-Bird Tail Creek-Surrounding Country-Shell River-Country North to Fort Pelly-Indian Farm-General Character of Soil-A Desert changed to a Paradise—Timber for Building Purposes—Where Located-Building Stone-Brick Clays—Water Supply near Winnipeg.
The eastern boundary of Manitoba is still undefined, but as originally formed, its limit was the 95th Meridian, which touches the Lake of the Woods. On the south, the International Boundary separates it from Minnesota and Dakota. Its western boundary is about 101°20' west long., and its northern, lat. 53o. Within these limits is comprised a total area of about 50,000 square miles, but that part of the country in the vicinity of Lakes Manitoba and Winnipegoosis, is low and marshy.
Its general character is that of a level plain, sloping gently to the north, and becoming swampy as we approach the lake basins. The greater part is included in the First Prairie Steppe, defined in the preceding chapter. This includes Lakes Winnipeg, Manitoba, and Winnipegoosis, and the low lying lands in their vicinity; that part of the Red River Valley, north of the International Boundary; and the Assiniboine Valley for twentyfive miles west of Portage la Prairie. The whole of this district was evidently at one time a lake basin, and the present rich coils are largely derived from the silts deposited during a long series of years, when the present surface was under water. These rich alluviums have been the theme of many writers, and it is not necessary for me to enlarge on their fertility, or capacity for growing grain crops continuously. Suffice it to say that the cause of the poor water and alkaline soil in numerous localities, can be traced, in every instance, to the exceeding richness of the soil, and as long as it retains its salts, so long will it be noted for fertility.
The following extracts from the Report of Dr. George M. Dawson, Geologist and Naturalist to the British North American Boundary Commission, will be found of great interest, as giving an exact account of the region in question from the standpoint of a competent observer :
THE RED RIVER PRAIRIE.”
“ Of the alluvial prairie of the Red River, much has already been said, and the uniform fertility of its soil cannot be exaggerated. The surface, for a depth of two to four feet, is a dark mould, composed of the same material as the subsoil, but mingled with much vegetable matter. Its dark color is, no doubt, in part due to the gradual accumulation of the charred grasses left by the prairie fires. The soil may be said to be ready for the plough, and in turning the tough thick prairie sod, the first year, a crop of potatoes may be put in, though it is not efficiently broken up till it has been subjected to a winter's frost. When the sod has rotted, the soil appears as a light friable mould easily worked, and most favorable for agriculture. The marly alluvium underlying the vegetable mould, would in most countries be considered a soil of the best quality, and the fertility of the ground may therefore be considered as practically inexhaustible.
“ The area of this lowest prairie has been approximately stated as 6,900 square miles, but of this the whole is not at present suited to agriculture. Small swamps are scattered pretty uniformly over its surface, and in some places very large areas of swampy land occur, as will be seen on reference to the large map of Manitoba, lately published by the Government. The greater part of these swamps are,
however, so situated as to be easily drained, either into the Red River or some of its tributaries, which are usually depressed thirty or forty feet below the level of the surface. At present, the swamps in the vicinity of the settlements are made to yield supplies of natural hay ; and until haygrass is sown and regularly cultivated, the “hay-swamps” will continue to be a necessary part of the economy of the settler. The wide overflow of these swamps in the spring, when the season is wet, or when the dissolution of the winter's snow takes place very rapidly, is shown by the large area often found to be strewn with the dead shells of fresh-water molluscs, chiefly of the genus Limnaea. .
“ As a measure of the possible agricultural capacity of this great valley, take one-half of the entire area, or 3,400 square miles, equalling 2,176,000 acres, and, for simplicity of calculation, let it be supposed to be sown entirely in wheat. Then, at the rate of seventeen bushels per acrewhich, according to Prof. Thomas, is the average yield for Minnesota--the crop of the Red River Valley would amount to 40,992,000 bushels.
“ The wooded area of this lowest Prairie Steppe is quite small. The Red River and its tributaries are fringed with trees, of which Oak (Quercus macrocarpa, var.), Elin (Ulmus Americana), Poplar (Populus tremuloides, et balsamifera), and Ashleaved Maple (Negundo aceroides), are the most abundant. In some places the trees attain a large size, and the Oak woods bordering many of the streams are especially beautiful. Much of the best timber has, however, already been culled out, and it is yearly decreasing, without any systematic attempt for its preservation. The steamers running on the Red River are among the largest consumers. Away from the immediate borders of the streams, the prairie, though covered with luxuriant sod, is absolutely treeless. It is fortunately the case, however, that the Red River valley is bordered on the east by the forests already described, and on the west by the wooded district of Pembina Mountain and its northern extensions.”
The Pembina Mountain is par excellence the ancient beach in the valley of Lake Winnipeg. Dr. Owen describes it as it occurs a few miles south of the 49th Parallel. “After a hot and fatiguing ride over the plains, we arrived an hour after sunset at the foot of the Pembina Mountain. In the twilight, as we stood at our encampment on the plain, it looked as if it might be 800 feet or more in height; but in the morning, by broad daylight, it seemed less. When I came to measure it, I was somewhat surprised that it did not exceed 210 feet. I observed on this as on many other occasions, that a hill rising out of a level plain, appears higher than it really is, especially when, as in this case, the trees on its flank and summit are of small growth. Pembina Mountain is, in fact, no mountain at all, nor yet a hill. It is a terrace of a table-land, the ancient shore of a great body of water, that once filled the whole of the Red River Valley. On its summit it is quite level and extends so, for about five miles westward, to another terrace, the summit of which, I was told, is level with the great Buffalo Plains, that stretch away toward the Missouri, the hunting grounds of the Sioux and the Half-breed population of Red River.
“Instead of being composed of ledges of rock, as I was led to suppose, it is a mass of incoherent sand, gravel, and shingle so entirely destitute of cement that with the hand alone a hole several feet deep may be excavated in a few minutes. The Pembina River has cut through this material a deep narrow valley, but little elevated above the adjacent plain.” Fifteen miles north of the Boundary Line, the
escarpment rises by four distinct terraces one over the other, three of which are from twenty to twenty-five feet high. Beyond this there is a gradual ascent of two miles, covered more or less with boulders, before the level of the next plateau is reached. It runs northwesterly from a point about thirty miles west of Red River, and merges into the Riding Mountain, west of the head of Lake Manitoba. In front of this broken escarpment, there are numerous marshes and pools of water which, north of the Assiniboine, prevent settlement for long distances. In rear, or to the west of this marshy tract, sand hills and sandy slopes rise one over the other, until the level of the plateau is attained. This plateau is the Second Prairie Steppe.
Riding Mountain rises from the lower plain at its southeastern termination by three successive steppes, each one separated from the other by a gently sloping plateau. The greater part of the mountain is densely covered with forest. On the ridges the soil is dry and gravelly and precisely like that of Pembina Mountain.
High above the Pembina Mountain the steppes and plateaux of the Riding and Duck Mountains rise in well defined succession. On the southern and western slopes of these ranges the terraces are distinctly defined; on the northeast and north sides they present a precipitous escarpment which is elevated fully 1,000 feet above Lake Winnipeg, or more than 1,600 feet above the sea.
Standing on the edge of the escarpment of the Riding Mountain and looking in the direction of Dauphin Lake, a gulf, two or three miles wide, and some two hundred and fifty feet deep, is succeeded by two ranges, one lower than the other, of cone-shaped hills covered with boulders. The hills are parallel to the general trend of the escarpment. In some places they are lost on the plateaux on which they rest, in others they stand out as bold eminences, showing the extent of denudation which gave rise to them.