Saturday 8. The thermometer stood at twelve degrees below 0, that is at forty-two degrees below the freezing point: the wind was from the northwest. Captain Lewis with fifteen men went out to hunt the buffaloe; great numbers of which darkened the prairies for a considerable distance: they did not return till after dark, having killed eight buffaloe and one deer. The hunt was, however, very fatiguing, as they were obliged to make a circuit at the distance of more than seven miles; the cold too, was so excessive that the air was filled with icy particles resembling a fog, and the snow generally six or eight inches deep and sometimes eighteen, in consequence of which two of the party were hurt by falls, and several had their feet frostbitten.
Sunday 9. The wind was this day from the east, the thermometer at seven degrees above 0, and the sun shone clear: two chiefs visited us, one in a sleigh drawn by a dog and loaded with meat.
Monday 10. Captain Clarke who had gone out yesterday with eighteen men to bring in the meat we had killed the day before, and to continue the hunt, came in at twelve o'clock. After killing nine buffaloe and preparing that already dead, he had spent a cold disagreeable night on the snow, with no covering but a small blanket, sheltered by the hides of the buffaloe they had killed. We observe large herds of buffaloe crossing the river on the ice, the men who were frostbitten are recovering, but the weather is still exceedingly cold, the wind being from the north, and the thermometer at ten and eleven degrees below 0: the rise of the river is one inch and a half.
Tuesday 11. The weather became so intensely cold that we sent for all the hunters who had remained out with captain Clarke's party, and they returned in the evening several of them frostbitten. The wind was from the north and the thermometer at sunrise stood at twenty-one below 0, the ice in the atmosphere being so thick as to render the weather hazy and give the appearance of two suns reflecting each other. The river continues at a stand. Pocapsahe made us a visit to-day.
Wednesday, December 12. The wind is still from the north, the thermometer being at sunrise thirty-eight degrees below 0. One of the Ahnahaways brought us down the half of an antelope killed near the fort; we had been informed that all these animals return to the Black mountains, but there are great numbers of them about us at this season which we might easily kill, but are unwilling to venture out before our constitutions are hardened gradually to the climate. We measured the river on the ice, and find it five hundred yards wide immediately opposite the fort.
Thursday 13. Last night was clear and a very heavy frost covered the old snow, the thermometer at sun rise being twenty degrees below 0, and followed by a fine day. The river falls.
Friday 14. The morning was fine, and the weather having moderated so far, that the mercury stood at 0, captain Lewis went down with a party to hunt; they proceeded about eighteen miles, but the buffaloe having left the banks of the river they saw only two, which were so poor as not to be worth killing, and shot two deer. Notwithstanding the snow we were visited by a large number of the Mandans.
Saturday 15. Captain Lewis finding no game returned to the fort hunting on both sides of the river, but with no success. The wind being from the north, the mercury at sunrise eight degrees below 0, and the snow of last night an inch and a half in depth. The Indian chiefs continue to visit us to-day with presents of meat.
Sunday 16. The morning is clear and cold, the mercury at sunrise 22° below 0. A Mr. Haney with two other persons from the British establishment on the Assiniboin, arrived in six days with a letter from Mr. Charles Chabouilles, one of the company, who with much politeness offered to render us any service in his power.
Monday 17. The weather to-day was colder than any we had yet experienced, the thermometer at sunrise being 45° below 0, and about eight o'clock it fell to 74° below the freezing point. From Mr. Haney, who is a very sensible intelligent man, we obtained much geographical information with regard to the country between the Missouri and Mississippi, and the various tribes of Sioux who inhabit it.