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Show PANQULTCH LAKEâ€"MODERN BASALT. 199 A few miles southeast of this basaltic field is a picturesque lakelet, occupying- a depression in the plateau, called the Pan quitch Lakeâ€"a sheet of water about a mile and a half in length and a mile in width It is a delightful locality, both for the tourist and the geologist. Around it stand forests of pine (P. ponderosd), while farther up the slopes of the plateau are thickets of spruce and aspen. Broad and stately ravines, bearing sparkling streams from the higher levels open near its margin, and the traveler, weary of the desert wastes below, revels in the rank vegetation which clothes their rocky slopes. Through the brief summer the longest and richest grass carpets their floors and every knoll and sloping bank is a parterre of the gayest flowers. Around this lake the volcanic strata are seen resting upon the sedi-mentaries; in short, it is a locality where the eruptive rocks have diminished in thickness, and they gradually disappear southward and southeastward. To the west and southwest they continue still in immense bulk, with greater variety and stronger contrasts than in the northern part of the plateau. Llere the oldest eruptives are trachytic. They are finely displayed upon the northern side of the lake, where they form low cliffs or steep slopes, and an abrupt canon entering from the northwest still more clearly lays them open to view. As we approach the lake from the northeast (the usual route), the instant we reach the summit of the hill from which we first see the. expanse of its surface, a most conspicuous object upon the south side of the lake immediately attracts the attention. It is a flood of basalt so recent and so fresh in its aspect that we wonder why there is no record or tradition of its eruption. It is dense black, and its ominous shade is rendered still more conspicuous by the lively colors of the sedimentary rocks and soil around it. We see at first only the end of a grand coulee, but beyond it rise rough, angry knolls and mountainous waves as black as midnight, telling of more beyond. Riding to the base of it, we find it to be composed of numberless fragments, ranging in size from a cubic foot to many cubic yards, piled up in strange confusion. A continuous bed or sheet is nowhere to be seen; nothing but this coarse rubble, looking like an exaggerated pile of anthracite dumped from the cars at the terminus of a great coal railway. A close inspection confirms this impression of recency |