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Rh seasons. These trails are carefully flanked at favorable intervals with little bastions and semicircular breastworks of loose stones, mementoes of Indian skill and strategy. Aside from any known or prospective material resource, the district of the lakes, with its dense forests and weird deserts, picturesque mountains and delightful valleys, and silent waters inclosed by perpendicular walls of mysterious formation, must ever be a scene of enjoyment for the tourist and lover of all that is grand, beautiful, and peculiar in Nature."

Thus does the observing traveler confirm the views of the student of geological science. The southern half of Eastern Oregon retains yet some of the features of the undrained lake districts of Oregon and Washington.

That portion of Oregon and Washington which lies west of the Cascades is part of a great trough, extending from the Straits of Fuca to the Bay of San Francisco. It is not, like Eastern Oregon, elevated above the original sea-bed by immense deposits of volcanic matter; but its older rocks are buried from sight by deposits of the Tertiary and post-Tertiary periods.

There is a curious glimpse into the pre-historic record of man given by the fossils of the Wallamet Valley. For instance, the teeth and tusks of the elephant have been found in Linn, Polk, and Clackamas counties, at no great depth below the surface—as in three instances they were discovered by men engaged in digging mill-races, probably from eight to twelve feet in depth. Side by side with this fact, is the one that at a similar depth some rude stone carvings have been discovered, buried in the alluvial soil of the Lower Wallamet, about two miles above its junction with the Columbia, in Columbia County. Stranger still, there