Since the date of my former Letter, I have been so much engaged in the amusements of the country, and the use of my brush, that I have scarcely been able to drop you a line until the present moment. Before I let you into the amusements and customs of this delightful country however, (and which, as yet, are secrets to most of the world), I must hastily travel with you over the tedious journey of 2000 miles, from St. Louis to this place; over which distance one is obliged to pass, before he can reach this wild and lovely spot. The Missouri is, perhaps, different in appearance and character from all other rivers in the world; there is a terror in its manner which is sensibly felt, the moment we enter its muddy waters from the Mississippi. From the mouth of the Yellow Stone River, which is the place from whence I am now writing, to its junction with the Mississippi, a distance of 2000 miles, the Missouri, with its boiling, turbid waters, sweeps off, in one unceasing current; and in the whole distance there is scarcely an eddy or resting-place for a canoe. Owing to the continual falling in of its rich alluvial banks, its water is always turbid and opaque; having, at all seasons of the year, the colour of a cup of chocolate or coffee, with sugar and cream stirred into it. To give a better definition of its density and opacity, I have tried a number of simple experiments with it at this place, and at other points below, at the results of which I was exceedingly surprised. By placing a piece of silver (and afterwards a piece of shell, which is a much whiter substance) in a tumbler of its water, and looking through the side of the glass, I ascertained that those substances could not be seen through the eighth part of an inch; this, however, is in the spring of the year, when the freshet is upon the river, rendering the water, undoubtedly, much more turbid than it would be at other seasons; though it is always muddy and yellow, and from its boiling and wild character and uncommon colour, a stranger would think, even in its lowest state, that there was a freshet upon it. For the distance of 1000 miles above St. Louis, the shores of this river (and, in many places, the whole bed of the stream) are filled with snags and raft, formed of trees of the largest size, which have been undermined by the falling banks and cast into the stream; their roots becoming fastened in the bottom of the river, with their tops floating on the surface of the water, and pointing down the stream, forming the most frightful and discouraging prospect for the adventurous voyageur. (See +plate+ 4.) Almost every island and sand-bar is covered with huge piles of these floating trees, and when the river is flooded, its surface is almost literally covered with floating raft and drift wood which bid positive defiance to keel-boats and steamers, on their way up the river.