The evening was fine, the sky being very clear, and I obtained an immersion of the third satellite, with a good observation of an emersion of the first; the latter of which gives for the longitude, 121° 02' 43"; the latitude, by observation, being 45° 06' 45". The night was cold--the thermometer during the observations standing at 9°.
28th.--The sky was clear in the morning, but suddenly clouded over, and at sunrise it began to snow, with the thermometer at 18°.
We traversed a broken high country, partly timbered with pine, and about noon crossed a mountainous ridge, in which, from the rock occasionally displayed, the formation consists of compact lava. Frequent tracks of elk were visible in the snow. On our right, in the afternoon, a high plain, partially covered with pine, extended about ten miles, to the foot of the Cascade mountains.
At evening we encamped in a basin narrowly surrounded by rocky hills, after a day's journey of twenty-one miles. The surrounding rocks are either volcanic products, or highly altered by volcanic action, consisting of quartz and reddish-colored silicious masses.
29th.--We emerged from the basin, by a narrow pass, upon a considerable branch of Fall river, running to the eastward through a narrow valley. The trail, descending this stream, brought us to a locality of hot springs, which were on either bank. Those on the left, which were formed into deep handsome basins, would have been delightful baths, if the outer air had not been so keen, the thermometer in these being at 89°. There were others on the opposite side, at the foot of an escarpment, in which the temperature of the water was 134°. These waters deposited around the spring a brecciated mass of quartz and feldspar, much of it of a reddish color.
We crossed the stream here, and ascended again to a high plain, from an elevated point of which we obtained a view of six of the great peaks--Mount Jefferson, followed to the southward by two others of the same class; and succeeding, at a still greater distance to the southward, were three other lower peaks, clustering together in a branch ridge. These, like the great peaks, were snowy masses, secondary only to them; and, from the best examination our time permitted, we are inclined to believe that the range to which they belong is a branch from the great chain which here bears to the westward. The trail, during the remainder of the day, followed near to the large stream on the left, which was continuously walled in between high rocky banks. We halted for the night on a little by-stream.