The New International Encyclopædia/Cascade Range

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CASCADE RANGE. A range of mountains in the western United States and Canada forming a northward continuation of the Sierra Nevada Range (Map: Washington, C 6). It begins in Northern California near the Oregon boundary and extends across the latter State and Washington into British Columbia, where the line of elevations is continued by many small groups which are deeply intersected and eroded by river and lake systems. Its direction in the United States is nearly north and south, parallel to the Pacific Coast; in Oregon the main axis of elevations lies about 100 miles from the coast, while in Washington the distance increases to 150 miles. The limits of the Cascade Range in British Columbia are not clearly defined. The name, however, is commonly assigned to the entire plateau region stretching across the province from southeast to northwest, which is limited on the east by the lofty ranges of the Rocky Mountains, and on the west by the Island Range. The southern section of the range is crossed by the Columbia River and by the Klamath River, both of which have cut deep gorges. In British Columbia the Fraser River occupies an extensive cañon, where it passes across the range to discharge into the Strait of Georgia.

The Cascade Range in its southern section is marked by extreme ruggedness of outline and by some of the loftiest summits in the United States. In the Shasta group of California, which defines its limit to the south, are Mount Shasta, 14,510 feet, and several other peaks over 10,000 feet in height. In Oregon, it includes Mount Hood, 11,934 feet; Mount Jefferson, 10,200 feet; and Mount Pitt, 9760 feet; while in Washington is the magnificent cone of Mount Rainier (Mount Tacoma), 14,526 feet, with many peaks of lesser altitude, including Mount Baker, 10,500; Mount Saint Helens, 9750; and Mount Adams, 9570 feet. The British Columbian section contains no notable elevations, its character being rather that of a plateau dissected by numerous rivers, with a few prominences rising above the surface to altitudes of 6000 or 7000 feet. The loftier summits of the Cascade Range are extinct volcanoes, and carry heavy snow-fields and glaciers. Igneous and volcanic rocks with Paleozoic strata constitute the central mass, while later sediments form the flanks. Its slopes, in part forested with firs, pine, and hard wood, are drained by the Columbia, Klamath, and Fraser rivers and by a large number of smaller streams, all of which discharge finally into the Pacific Ocean. See topography of Oregon, Washington, and British Columbia.