By these experiments, however, the superficial current or stratum only was indicated, and as we had reason to suppose that this stratum was more impeded by friction against the inferior surface of the ice than it would be by the atmosphere, it became an object to ascertain the average velocity of the different depths. With this view a staff ten feet long was made to float vertically, by means of a weight attached to its inferior extremity; a line of one hundred and seventy-eight feet in length was run out by this arrangement, during the following intervals of time, in four experiments, viz. 1′ 21″--1′ 21″--1′ 19″--1′ 21″, of which the mean is 1′ 20-1/2″, which would seem to indicate a current of the velocity of 1 mile 893 yards 1 foot per hour. Thus the average velocity of ten feet in depth of the current of the Missouri, is greater by almost 452 yards in a single hour, than {173} that of a superficial stratum of about six inches depth, during the ice-bound state of the river. During these experiments the atmosphere was nearly calm. 25th. Cooked for dinner the entire hump of a bison, after the manner of the Indians; this favourite part of the animal was dissected from the vertebræ, after which the spinous processes were taken out, and the denuded part was covered with skin, which was firmly sewed to that of the back and sides of the hump; the hair was burned and pulled off, and the whole mass exhibiting something of a fusiform shape, was last evening placed in a hole dug in the earth for its reception, which had been previously heated by means of a strong fire in and upon it. It was now covered with cinders and earth, to the depth of about one foot, and a strong fire was made over it. In this situation it remained until it was taken up for the table to-day, when it was found to be excellent food. Mr. Lisa and family dined with us by invitation. That we have sometimes food in great sufficiency, the provision upon our table this day will sufficiently attest. It consisted of the entire bison hump, above mentioned; the rump of a bison roasted, boiled bison meat, two boiled bison tongues, the spinous processes roasted in the manner of spare-ribs, sausages made of minced tender loin and fat, &c. It is true that we have no vegetables whatever, but having been so long estranged from them, we scarcely regret their absence. Their place is supplied by excellent wheat flour, of which our cook prepares us bread fully equal, in point of excellence, to any that we have ever eaten. The above repast was prepared for eleven persons, of whom two were ladies.[201] The collation was succeeded by coffee as a desert. February 28th. I ascertained the temperature of spring water, which, however, was somewhat exposed to the atmosphere, but in a shaded situation, and in a ravine, to be 47°; that of the atmosphere being at {174} the same time 56°, and that of the river 32°, of Fahrenheit's scale.