192 Expedition to the 



present low water. We availed ourselves of a long vacancy 

 in the ice to float a porter bottle, to which the proper speci- 

 fic gravity was given, by partially filling it with water, it was 

 attached to a cord of one hundred and twenty-two feet io 

 length ; it floated this distance in six successive experiments 

 in the following several times 1' 07"—-!' 04" — 1' 07 1-2" — 

 1' 05-— V 07"— 1 07", the mean of which is 1' 06 1-2" near- 

 ly, giving a velocity of 1 mile 441 yards 1 1-2 feet per hour. 



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, dur- 

 ing 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 ve- 

 locity 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 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 vertebrae, 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 



♦ 



