Page:Oregon Historical Quarterly volume 13.djvu/15

Rh water from the mountains than it did at this time, for its numerous tributaries were fed by many melting glaciers still lingering from the age of ice. In some places where the river gorge was narrow, as at the Cascades, the waters must have been very deep. While beyond The Dalles, near the mouth of the Des Chutes, there was a large "lake like extension of the river" where this great volume of water could quietly write, its own history, for here it deposited layer after layer of sediment in which it carefully buried the bones and teeth of the animals that roamed on its shores or were washed down from the mountains when this lake stood over two hundred and fifty feet above the present surface of the Columbia. At this time, too, the Walla Walla Valley and the Valley of the Yakima were flooded and were writing other chapters of the same old history.

If the encroachment of the sea crowded back the Columbia until it produced such high water in Eastern Oregon and Washington, what was its effect upon the valley of the Willamette? When the waters stood over three hundred feet above their present level at the mouth of the Willamette they evidently covered the whole valley from the coast mountains to the Cascades and from the Scappoose Mountains on the north, to the hills that surround Eugene on the south. And it was a beautiful body of water, one hundred and twenty miles in length and fifty miles or more in width, for not only was the level valley covered but the waters had quietly climbed the lower slopes of the foothills until they stood far above the present altitude of the church spires of Portland and Salem.

In the northern part of this Willamette Sound the Chehalem Mountains formed a fine wooded island from which could be seen the broad bay that covered Tualatin plains, on whose waters one might have sailed more than a hundred feet above the present towns of Forest Grove and Hillsboro. Across a narrow straight from Chehalem was the island of the Dundee Hills and from both of these elevations could be seen the great expanse of waters and the many distant snowpeaks of the Cascade Mountains. Perhaps the largest of these islands was