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Rh themselves, in general, stand on the eastern side of the summit of the range. A covering of lava, in the form of basaltic rock, conceals from sight the record we have referred to, except where by the action of water the pages of the book have been cut through from cover to cover—from ocean-bed to overlying basalt.

For a distance of sixty miles east of Dalles this last overflow may be traced, growing thinner and thinner, until it becomes a mere capping on the hills. Underneath it all is sedimentary, except the interruptions, several in number, of the older outflows of lava. It is owing to the large extent to which volcanic ash enters into the composition of the earth and soil of this portion of Oregon and Washington that both earth and water are so often strongly alkaline. It forms a soil inexhaustible in fertility, and particularly adapted to the growth of cereals; but owing to its elevation, and to the depth of the streams below the surface, together with a dry climate, is difficult of adaptation to the uses of the grain-raiser.

Apropos of the geological formation of Eastern Oregon, Mr. J. Wassen writes in the Overland Monthly, for February, 1869, the following:

"Coming from the north-east, the Blue Range of Oregon, the Cascade Range from the north, and the Sierra from the south, blend into or form a vast steppe or table-land of lava and sage-fields, interspersed with a score of lakes, in size varying from five to forty miles in length, and proportionate width. This high separating belt of land and water commences at the Owyhee River, and extends westward to the mountains, running at right angles to the ocean—a length of three hundred miles, and an average breadth of one hundred