Monday 15.  We proceeded under a fine breeze from the south, and clear pleasant weather.  At seven miles we reached the lower point of an island in a bend to the south, which is two miles in length.  Captain Clarke, who went about nine miles northward from the river reached the high grounds, which, like those we have seen, are level plains without timber; here he observed a number of drains, which descending from the hills pursue a northeast course, and probably empty into the Mouse river, a branch of the Assiniboin, which from Indian accounts approaches very near to the Missouri at this place.  Like all the rivulets of this neighbourhood these drains were so strongly impregnated with mineral salts that they are not fit to drink.  He saw also the remains of several camps of Assiniboins; the low grounds on both sides of the river are extensive, rich, and level.  In a little pond on the north, we heard for the first time this season the croaking of frogs, which exactly resembles that of the small frogs in the United States:  there are also in these plains great quantities of geese, and many of the grouse, or prairie hen, as they are called by the N.W. company traders; the note of the male, as far as words can represent it, is cook, cook, cook, coo, coo, coo, the first part of which both male and female use when flying; the male too drums with his wings when he flies in the same way, though not so loud as the pheasant; they appear to be mating.  Some deer, elk, and goats were in the low grounds, and buffaloe on the sand beaches, but they were uncommonly shy; we also saw a black bear, and two white ones.  At fifteen miles we passed on the north side a small creek twenty yards wide, which we called Goatpen creek, from a park or enclosure for the purpose of catching that animal, which those who went up the creek found, and which we presume to have been left by the Assiniboins.  Its water is impregnated with mineral salts, and the country through which it flows consists of wide and very fertile plains, but without any trees.  We encamped at the distance of twenty-three miles, on a sandpoint to the south; we passed in the evening a rock in the middle of the river, the channel of which a little above our camp, is confined within eighty yards.

Tuesday 16.  The morning was clear, the wind light from the S.E.  The country presents the same appearance of low plains and meadows on the river, bounded a few miles back by broken hills, which end in high level fertile lands, the quantity of timber is however increasing.  The appearance of minerals continues as usual, and to-day we found several stones which seemed to have been wood, first carbonated and then petrified by the water of the Missouri, which has the same effect on many vegetable substances.  There is indeed reason to believe that the strata of coal in the hills cause the fire and appearances which they exhibit of being burned.  Whenever these marks present themselves in the bluffs on the river, the coal is