examination; the width of the north branch is two hundred yards, that of the south is three hundred and seventy-two.  The north, although narrower and with a gentler current, is deeper than the south:  its waters too are of the same whitish brown colour, thickness, and turbidness:  they run in the same boiling and rolling manner which has uniformly characterized the Missouri; and its bed is composed of some gravel, but principally mud.  The south fork is deeper, but its waters are perfectly transparent:  its current is rapid, but the surface smooth and unruffled; and its bed too is composed of round and flat smooth stones like those of rivers issuing from a mountainous country.  The air and character of the north fork so much resemble those of the Missouri that almost all the party believe that to be the true course to be pursued.  We however, although we have given no decided opinion, are inclined to think otherwise, because, although this branch does give the colour and character to the Missouri, yet these very circumstances induce an opinion that it rises in and runs through an open plain country, since if it came from the mountains it would be clearer, unless, which from the position of the country is improbable, it passed through a vast extent of low ground after leaving them:  we thought it probable that it did not even penetrate the Rocky mountains, but drew it sources from the open country towards the lower and middle parts of the Saskashawan, in a direction north of this place.  What embarrasses us most is, that the Indians who appeared to be well acquainted with the geography of the country, have not mentioned this northern river; for “the river which scolds at all others,” as it is termed, must be according to their account one of the rivers which we have passed; and if this north fork be the Missouri, why have they not designated the south branch which they must also have passed, in order to reach the great falls which they mention on the Missouri.  In the evening our parties returned, after ascending the rivers in canoes for some distance, then continuing on foot, just leaving themselves time to return by night.  The north fork was less rapid, and therefore afforded the easiest navigation:  the shallowest water of the north was five feet deep, that of the south six feet.  At two and a half miles up the north fork is a small river coming in on the left or western side, sixty feet wide, with a bold current three feet in depth.  The party by land had gone up the south fork in a straight line, somewhat north of west for seven miles, where they discovered that this little river came within one hundred yards of the south fork, and on returning down it found it a handsome stream, with as much timber as either of the larger rivers, consisting of the narrow and wide-leafed cottonwood, some birch and box-alder, amid undergrowth of willows, rosebushes, and currants:  they also saw on this river a great number of elk and some beaver.