The next day we reached the Big Muddy River. The crossing was at a difficult ford, and we were all highly gratified at the zeal and efficiency of one of the Blackfeet, who pulled as steadily at the rope as any man of my party.
Before leaving the Big Muddy I had a long conversation with the White Man’s Horse, the chief of the war party of Blackfeet. He had frequently visited the Bitter Root valley, and stolen horses from the Flatheads. He observed, “I take the first Flathead horse I come to; it is sure to be a good one.” He and one of his men had just returned from the Flathead country, and they gave a very favorable description of the route, assuring me, pointing to my wagons and Pembina carts, that there would be no difficulty in taking them through the mountains. The country between Fort Union and this point is broken and rolling, with occasional formations of the mauvaise terre and outcroppings of sandstone. On the Big Muddy there is quite a large and open valley of a very good soil and excellent grass, with a very heavy growth of cottonwood near its junction with the Missouri.
On starting from the Big Muddy on the 14th of August, the command was in most excellent condition and spirits. Two of the mule teams were strengthened by an additional pair of mules, and the wagons were somewhat overloaded; for I determined to take nearly all my provisions along, so there should be no possibility of suffering for want of food, even though the depot of provisions in the Bitter Root valley had not been established by Lieutenant Saxton. We made eleven and a half miles, and encamped at a most beautiful point in the midst of luxuriant grass. The day was very sultry, some rain fell, and one ox died from the heat.
August 15. Excellent road all day. Crossed Poplar River and encamped on the west side, distance eighteen miles. I now felt the importance of renovating my health in order to prepare for the mountain work. It had been my custom thus far to continue at work till midnight, and to be up with the first in the morning.
August, 16. The road to-day was over the level river-bottom of the Missouri. Timber in sight all day, the route running through timber for about a mile. Reached a camp where there was excellent water, grass, and abundance of timber at five o’clock, making twenty three and two thirds miles. I issued this evening an order directing every person in the expedition, so far as it was consistent with his duties, to walk a portion of the way each day; for in approaching the mountains my effort was that the animals should be increasing rather than diminishing in flesh, and our experience had taught us that, by care in all these particulars, long marches could be made and the animals improved each day.
August 17. Made fifteen miles to-day, and camped on the Missouri at two o’clock. The road was over the level river-bottom. Much side work has been done since leaving the Big Muddy by Lieutenant Grover, Mr. Lander, and Mr. Tinkham, and the meteorological observations have been as numerous as they were on the route up to Fort Union. We organized to-day a day guard for the care of the animals, the object being to keep them in the best grazing without picketing as long as possible.
August 18. Passed through to-day villages of prairie dogs. Crossed the Porcupine River about five miles from camp. Encamped on Milk River, sixteen miles being the day’s march. Here we determined to remain a day to prepare charcoal for the blacksmith, and to make observations for the geographical position of its mouth, which is considered a very important point in the survey. Our camp was surrounded by a large grove of cottonwood, and near it was a delightful spring of water. The valley of Milk River is wide and open, with a heavy growth of cottonwood as far as the eye can reach, which is also to be found along the adjacent shores of the Missouri.
At this camp, which I named Camp Atchison, in honor of the acting Vice-President, I reduced to writing, and issued in an order, the instructions for the government of the expedition and the distribution of duties, under which we had been moving by my verbal instructions from the Big Muddy River. I availed myself of this opportunity to express my sense of the services of the several members of my party. On the 19th there was some little alarm in camp in consequence of false reports about the vicinity of a war party of Blackfeet.
We left Camp Atchison on the 20th, and after moving fifteen miles reached a very pleasant camp, with excellent grass, wood, and water. In the evening there was a very heavy thunder-storm. My order was read to the gentlemen of the party this evening, and was the subject of general congratulation, and not a little mischievous by-play or joking.
August 21. This morning was clear, cool, pleasant, and delightful for moving. Engineer parties, both yesterday and to-day, have been actively at work getting in the country bordering the route of the main party. I dispatched a small party across Milk River to Panther Hill to observe the country. Game was very abundant; plenty of buffalo, antelope, and beaver. A heavy rain and thunder-storm occurred about noon. Wild horses were reported as having been seen to-day by the reconnoitring parties. A fine eagle was shot and brought in to Dr. Buckley, our naturalist. To my exceeding regret, I found that there were points arising regarding the relations of army officers and civilians, and I concluded that the only way to overcome all difficulty was to pursue a firm, steady course, according to the terms of my written order. The distance to-day was seventeen and two thirds miles.