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The Earthquake in Japan: Judson Daland

The Geographic Setting of Muscle Shoals: K. C.

McMurry

The Importance of Foreign Trade to New England:

G. B. Roorbach ...

The Possibilities of Cattle Production in Venezuela:

Preston E. James

The Public Markets of Finland: Eugene Van Cleef
The Russian Antarctic Expedition under T. H. Bell-

ingshausen, 1819-21: Jules de Schokalsky ....
The Topography of a Canadian Watershed: J.

Monroe Thorington
Thorington, J. Monroe: The Topography of a

Canadian Watershed

Thorington, J. Monroe: Heights of Athabaska....

Transportation Adjustments in the Railway En-

trances and Terminal Facilities at Montreal:

Clarence F. Jones

Trotter, Spencer: South by East. Being Reflections

Along an Old Line of Travel

Van Cleef, Eugene: The Public Markets of Finland

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Photo by Interprovincial Survey Fig. 1.-THE COLUMBIA ICEFIELD: CANADA'S TRI-OCEANIC DIVIDE

THE TOPOGRAPHY OF A CANADIAN WATERSHED

(The Tri-oceanic Divide of the Columbia Icefield.)

By J. MONROE THORINGTON, M. D.

"A new world was spread at our feet; to the westward stretched a vast ice-field probably never before seen by human eye, and surrounded by entirely unknown, unnamed and unclimbed peaks. From its vast expanse of snow the Saskatchewan glacier takes its rise, and it also supplies the head-waters of the Athabasca; while far away to the west, bending over in those unknown valleys glowing with the evening light, the level snows stretched, to finally melt and flow down more than one channel into the Columbia River, and thence to the Pacific Ocean."

J. NORMAN COLLIE, 1898. The use of travelling is to regulate imagination by reality, and instead of thinking how things may be to see them as they are."

SAMUEL JOHNSON. The Continent of North America possesses two hydrographic apices which are remarkable for the river systems extending therefrom. In each of these areas occurs a watershed of the triple-divide type, whose streams form great and lengthy rivers, flowing enormous distances to terminate in widely separated bodies of water.

The southerly of these interesting regions is found, near Latitude 43, in the Wind River Mountains of Wyoming, south of Yellowstone National Park. Here rises the Snake River, flowing to the Columbia, its waters carried through British Columbia and emptying into the Pacific at the northwest corner of Oregon. Not many miles distant are sources of Green River, flowing southwest to the Colorado and reaching the Gulf of California. Eastward, branching headwaters of the Missouri find their way to the Mississippi basin and the far-off gulf of Mexico.

Less well known is the Canadian watershed to be found in Latitude 52. There, in a region extensively glaciated, are sources of river systems whose waters make their way for hundreds of miles, by winding, devious routes to three separate oceans.

The Rocky Mountains of Canada form the Alberta-British Columbia Boundary and extend northward, from the Montana line, at the 114th Parallel, until the 120th Parallel is reached, near Latitude 54, and the range become subalpine. Great icefields mantle the Continental Divide between the Canadian Pacific and the Canadian National Railroads, the scenic grandeur culminating in the Columbia Icefield, in Latitude 52°, 12'.

This icefield, the largest known in Canada, containing approximately 150 square miles, forms an unusually compact triple-divide. From its snows, on the Continental Divide and attaining an elevation of 10,000 feet over a large area, are formed the headwaters of the Athabaska, which, by way of Great Slave Lake, joins the Mackenzie system whose delta is beyond the Arctic Circle. Western ice-tongues supply Bush River, tributary to the Columbia and reach ing the Pacific. From many converging streams on the eastern slope is formed the Saskatchewan River, emptying into Lake Winnipeg whence the Nelson River continues the drainage to Hudson Bay and the Atlantic Ocean.

Thus do two great mountain uplifts form the drainage sources for much of Continental America between Mexico and Alaska.

The two water-partings possess no little of historic interest. In 1805, the Lewis and Clark Expedition, reaching the forks of the Missouri, pioneered the Jefferson River and crossed to the Clearwater branch of the Columbia on their way to the Pacific Coast. Only a little later, Canadian fur-traders, in 1807, made use of Howse Pass in travelling across the Rocky Mountains, from the North Saskatchewan—the Kootenay Plains—to the Columbia valley. In 1811, the Athabaska Pass was opened by David Thompson of the Northwest Company and served for many years as a much-frequented route between Athabaska trading-posts-Fort Edmonton, Henry House, and Jasper House—and the Columbia loop.

Anyone who has even superficially examined the map of a Continent, will realize that rivers of any length possess sources in elevated portions of the earth's surface. It is the land uplift, usually a mountain region, in which occurs the greatest precipitation; the ranges and inland table-lands, or even lofty plateaus, serve the further purpose of providing the potential energy, the vis a tergo, for stream flow. It will be further understood that such a region is topographically more complex than an area of coastal plain; and that, to unravel the complex features which a mountain range often possesses and which are frequently hidden, it is quite essential for

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