It was a serious enterprise, at the commencement of winter, to undertake the traverse of such a region, and with a party consisting only of twenty- five persons, and they of many nations--American, French, German, Canadian, Indian, and colored--and most of those young, several being under twenty-one years of age. All knew that a strange country was to be explored, and dangers and hardships to be encountered; but no one blenched at the prospect. On the contrary, courage and confidence animated the whole party. Cheerfulness, readiness, subordination, prompt obedience, characterized all; nor did any extremity of peril and privation, to which we were afterwards exposed, ever belie, or derogate from, the fine spirit of this brave and generous commencement. The course of the narrative will show at what point, and for what reasons, we were prevented from the complete execution of this plan, after having made considerable progress upon it, and how we were forced by desert plains and mountain ranges, and deep snows, far to the south, and near to the Pacific ocean, and along the western base of the Sierra Nevada, where, indeed, a new and ample field of exploration opened itself before us. For the present, we must follow the narrative, which will first lead us south along the valley of Fall river, and the eastern base of the Cascade range, to the Tlamath lake, from which, or its margin, three rivers go in three directions--one west, to the ocean; another north, to the Columbia; the third south, to California.

For the support of the party, I had provided at Vancouver a supply of provisions for not less than three months, consisting principally of flour, peas, and tallow--the latter being used in cooking; and, in addition to this, I had purchased at the mission some California cattle, which were to be driven on the hoof. We had 104 mules and horses--part of the latter procured from the Indians about the mission; and for the sustenance of which, our reliance was upon the grass which we should find, and the soft porous wood which was to be substituted when there was none.

Mr. Fitzpatrick, with Mr. Talbot and the remainder of the party, arrived on the 21st; and the camp was now closely engaged in the labor of preparation. Mr. Perkins succeeded in obtaining as a guide to the Tlamath lake two Indians--one of whom had been there, and bore the marks of several wounds he had received from some of the Indians in the neighborhood; and the other went along for company. In order to enable us to obtain horses, he dispatched messengers to the various Indian villages in the neighborhood, informing them that we were desirous to purchase, and appointing a day for them to bring them in.

We made, in the mean time, several excursions in the vicinity. Mr. Perkins walked with Mr. Preuss and myself to the heights, about nine miles distant, on the opposite side of the river, whence, in fine weather, an extensive view may be had over the mountains, including seven great peaks of the Cascade range; but clouds, on this occasion, destroyed the anticipated pleasure, and we obtained bearings only to three that were visible--Mount Regnier, St. Helens, and Mount Hood. On the heights, about one mile south of the mission, a very fine view may be had of Mount Hood and St. Helens. In order to determine their position with as much accuracy as possible, the angular distances of the peaks were measured with the sextant, at different fixed points from which they could be seen.

The Indians brought in their horses at the appointed time, and we succeeded in obtaining a number in exchange for goods; but they were relatively much higher here, where goods are plenty and at moderate prices, than we had found them in the more eastern part of our voyage. Several of the Indians inquired very anxiously to know if we had any dollars; and the horses we procured were much fewer in number than I had desired, and of thin, inferior quality; the oldest and poorest being those that were sold to us. These horses, as ever in our journey you will have occasion to remark, are valuable for hardihood and great endurance.

24th.--At this place one of the men was discharged; and at the request of Mr. Perkins, a Chinook Indian, a lad of nineteen, who was extremely desirous to "see the whites," and make some acquaintance with our institutions, was received into the party under my special charge, with the understanding that I would again return him to his friends. He had lived for some time in the household of Mr. Perkins, and spoke a few words of the English language.

25th.--We were all up early, in the excitement of turning towards home. The stars were brilliant, and the morning cold, the thermometer at daylight 26°.

Our preparations had been fully completed, and to-day we commenced our journey. The little wagon which had hitherto carried the instruments, I judged it necessary to abandon; and it was accordingly presented to the mission. In all our long traveling, it had never been overturned or injured by any accident of the road; and the only things broken were the glass lamps, and one of the front panels, which had been kicked out by an unruly Indian horse. The howitzer was the only wheeled carriage now remaining. We started about noon, when the weather had become disagreeably cold, with flurries of snow. Our friend Mr. Perkins, whose kindness had been active and efficient during our stay, accompanied us several miles on our road, when he bade us farewell, and consigned us to the care of our guides. Ascending to the uplands beyond the southern fork of the Tinanens creek, we found the snow lying on the ground in frequent patches, although the pasture appeared good, and the new short grass was fresh and green. We traveled over high, hilly land, and encamped on a little branch of Tinanens creek, where there were good grass and timber. The southern bank was covered with snow, which was scattered over the bottom; and the little creek, its borders lined with ice, had a chilly and wintry look. A number of Indians had accompanied us so far on our road, and remained with us during the night. Two bad-looking fellows, who were detected in stealing, were tied and laid before the fire, and guard mounted over them during the night. The night was cold, and partially clear.

26th.--The morning was cloudy and misty, and but a few stars visible. During the night water froze in the tents, and at sunrise the thermometer was at 20°. Left camp at 10 o'clock, the road leading along tributaries of the Tinanens, and being, so far, very good. We turned to the right at the fork of the trail, ascending by a steep ascent along a spur to the dividing grounds between this stream and the waters of Fall river. The creeks we had passed were timbered principally with oak and other deciduous trees. Snow lies everywhere here on the ground, and we had a slight fall during the morning; but towards noon the bright sky yielded to a bright sun.

This morning we had a grand view of St. Helens and Regnier: the latter appeared of a conical form, and very lofty, leading the eye far up into the sky. The line of the timbered country is very distinctly marked here, the bare hills making with it a remarkable contrast. The summit of the ridge commanded a fine view of the Taih prairie, and the stream running through it, which is a tributary to the Fall river, the chasm of which is visible to the right. A steep descent of a mountain hill brought us down into the valley, and we encamped on the stream after dark, guided by the light of fires, which some naked Indians, belonging to a village on the opposite side, were kindling for us on the bank. This is a large branch of the Fall river. There was a broad band of thick ice some fifteen feet wide on either bank, and the river current is swift and bold. The night was cold and clear, and we made our astronomical observation this evening with the thermometer at 20°.