and blotted out all forms of vegetable and animal life. The ages roll on, and once more living forms of plant and animal haunt the shores of these shallowing lakes. The oak, the yew, the willow, have left their prints in the sedimentary rocks, and the bones of new creations of animal life, such as the camel and the horse, accompany them. But these, too, in turn suffer extinction by violence,—the whole country being covered more than thirty feet deep in volcanic ashes. Indeed, deposits of volcanic ashes exist in East Oregon which are one hundred feet in depth.
After a long night of geological darkness, during which there seems to have been a subsidence of earthquake and volcanic outflow, life once more appears upon this portion of the earth in the forms of elephant, ox, horse, and elk, accompanied by such vegetable forms as were suitable for their subsistence. Still another period of death was to ensue before the framework of the present Oregon was perfected. And this time the desolation appears not to have come from fire, but from frost and flood. How long it continued, or what mighty seas of ice moved over the face of the earth, marking the hardest rock with glacial abrasion, none can tell. But to have so clearly written in the rocks of Oregon the geologic history of at least one continent, is most interesting to scientist and amateur alike. So far as can be seen, the Columbia River Valley must become the most desirable field for the student of the earth's history, and also of research into the record of prehistoric man. For here, somewhere hidden in these ancient pages of rock, must the beginning of man’s history be preserved, like that of God's other creatures, in tablets of stone.
From the brief sketch of Oregon's geologic history which has been given it will appear what the agency has been of those glistening white snow-peaks—Mounts Hood, St. Helen, Adams, Jefferson, and all the rest—in forming the Oregon and Washington of to-day. Time was when these mountains belched forth molten lava, and rained hot ashes over many miles of country on either side. For some reason—perhaps the direction of the prevailing winds—the ashes were chiefly deposited on the east side of the range. The volcanoes themselves, in general, stand on the east side of the summit of the range. A covering of
