26th.--Our general course was again south. The country consists of larger or smaller basins, into which the mountain waters run down, forming small lakes: they present a perfect level, from which the mountains rise immediately and abruptly. Between the successive basins, the dividing grounds are usually very slight; and it is probable that in the seasons of high water, many of these basins are in communication. At such times there is evidently an abundance of water, though now we find scarcely more than the dry beds. On either side, the mountains, though not very high, appear to be rocky and sterile. The basin in which we were traveling declined towards the southwest corner, where the mountains indicated a narrow outlet; and, turning round a rocky point or cape, we continued up a lateral branch valley, in which we encamped at night, on a rapid, pretty little stream of fresh water, which we found unexpectedly among the sage, near the ridge, on the right side of the valley. It was bordered with grassy bottoms and clumps of willows; the water partially frozen. This stream belongs to the basin we had left. By a partial observation to-night, our camp was found to be directly on the 42d parallel. To-night a horse belonging to Carson, one of the best we had in the camp, was stolen by the Indians.
27th.--We continued up the valley of the stream, the principal branch of which here issues from a bed of high mountains. We turned up a branch to the left, and fell into an Indian trail, which conducted us by a good road over open bottoms along the creek, where the snow was five or six inches deep. Gradually ascending, the trail led through a good broad pass in the mountain, where we found the snow about one foot deep. There were some remarkably large cedars in the pass, which were covered with an unusual quantity of frost, which we supposed might possibly indicate the neighborhood of water; and as, in the arbitrary position of Mary's lake, we were already beginning to look for it, this circumstance contributed to our hope of finding it near. Descending from the mountain, we reached another basin, on the flat lake bed of which we found no water, and encamped among the sage on the bordering plain, where the snow was still about one foot deep. Among this the grass was remarkably green, and to-night the animals fared tolerably well.