The discovery of Pinnacle pass left no question as to the route to be traversed in order to reach the mountains to the westward. We returned to Camp 12, and the following day, with Crumback and Lindsley to assist us, advanced our camp across Pinnacle pass and far down the western snow-slope. The day we crossed the pass was bright and clear in the morning, but clouds gathered around all the higher peaks about midday, vanishing again at nightfall. As it was desirable to occupy, for topographic and other purposes, a station on the top of the cliffs overlooking Pinnacle pass, we made an effort to reach the crest of the ridge by climbing up the steep scarp just at the divide, where the cliffs are lowest. While Crumback returned to Camp 12 for an additional load and Lindsley went ahead to discover a new camping place, Kerr and myself, taking the necessary instruments, began the ascent; but we found it exceedingly difficult. The outcrops of shale in the lower portion of the cliff furnished but poor foothold, and crumbled and broke away at every step. Once my companion, losing his support, slid slowly {132} down the slope in spite of vigorous efforts to hold on, and a rapid descent in the yawning chasm below seemed inevitable, when, coming to a slightly rougher surface, he was able to control his movements and to regain what had been lost. Climbing on, we came to the base of a vertical wall of shale several hundred feet high, and made a detour to the left where a cascade plunged down a narrow channel. We ascended the bed of the stream, which was sometimes so steep that the spray dashed over us, and reached the base of an overhanging cliff of conglomerate composed of well-worn pebbles. Above this rose a cliff of snow fifty feet or more in height, which threatened to crash down in avalanches at any moment. One small avalanche did occur during the ascent, and scattered its spray in our faces. Had a heavy avalanche formed, our position would have been exceedingly dangerous; but by taking advantage of every overhanging ledge, and watching for the least sign of movement in the snow above, we reached without accident a sheltered perch underneath an overhanging cliff near the base of the snow. We then discovered that clouds were forming on all the high mountains, and shreds of vapor blown over the crest of the cliff above told us that further efforts would be useless. Seeking a perch protected from avalanches by an overhanging cliff, we had a splendid view far out over the sloping snow-plain toward the west and of the mountains bordering Pinnacle pass on the south. My notes written in this commanding station read as follows: