17th.--The weather yesterday had not permitted us to make the observations I was desirous to obtain here, and I therefore did not move to-day. The people continued their target firing. In the steep bank of the river here, were nests of innumerable swallows, into one of which a large prairie snake had got about half his body, and was occupied in eating the young birds. The old ones were flying about in great distress, darting at him, and vainly endeavoring to drive him off. A shot wounded him, and, being killed, he was cut open, and eighteen young swallows were found in his body. A sudden storm, that burst upon us in the afternoon, cleared away in a brilliant sunset, followed by a clear night, which enabled us to determine our position in longitude 95 deg. 38' 05", and in latitude 39 deg. 06' 40". A party of emigrants to the Columbia river, under the charge of Dr. White, an agent of the government in Oregon Territory, were about three weeks in advance of us. They consisted of men, women, and children. There were sixty-four men, and sixteen or seventeen families. They had a considerable number of cattle, and were transporting their household furniture in large, heavy wagons. I understood that there had been much sickness among them, and that they had lost several children. One of the party who had lost his child, and whose wife was very ill, had left them about one hundred miles hence on the prairies; and as a hunter, who had accompanied them, visited our camp this evening, we availed ourselves of his return to the States to write to our friends. The morning of the 18th was very unpleasant. A fine rain was falling, with cold wind from the north, and mists made the river hills look dark and gloomy. We left our camp at seven, journeying along the foot of the hills which border the Kansas valley, generally about three miles wide, and extremely rich. We halted for dinner, after a march of about thirteen miles, on the banks of one of the many little tributaries to the Kansas, which look like trenches in the prairie, and are usually well timbered. After crossing this stream, I rode off some miles to the left, attracted by the appearance of a cluster of huts near the mouth of the Vermilion. It was a large but deserted Kansas village, scattered in an open wood, along the margin of the stream, chosen with the customary Indian fondness for beauty of scenery. The Pawnees had attacked it in the early spring. Some of the houses were burnt, and others blackened with smoke, and weeds were already getting possession of the cleared places. Riding up the Vermilion river, I reached the ford in time to meet the carts, and, crossing, encamped on its western side. The weather continued cold, the thermometer being this evening as low as 49 deg.; but the night was sufficiently clear for astronomical observations, which placed us in longitude 96 deg. 04' 07", and latitude 39 deg. 15' 19". At sunset, the barometer was at 28.845, thermometer 64 deg.