SUKFACE FEATURES . 49 



usually sloping very gently to the flood-plain. The flood- 

 plains of these valleys are in some respects unlike those 

 of other streams, for they usually have a slight but regular 

 slope from the valley-side to the stream without any appear- 

 ance of terraces; and yet much the larger part of the surface 

 of these plains is entirely above the reach of the highest 

 floods. Near the confluence of the two streams the valleys 

 are still further widened, and the slopes of their sides from 

 the uplands are very gentle. Below the confluence the 

 united valley has much the same appearance, and from 

 the distant high ridge, which separates it from that of the 

 Missouri river, the view is often very beautiful and extensive, 

 for the elevation at that distance from the river is upward of 

 two hundred feet above the Mshnabotany. From the point 

 where the Mshnabotany enters the great flood-plain of the 

 Missouri river, it meanders through it for many miles as a 

 tortuous, muddy canal, and Anally empties into the great 

 river within the State of Missouri. 



The two valleys throughout their entire length possess 

 considerable, but unromantic beauty; and the soil, both of 

 the valleys and the entire intervening uplands, possesses 

 remarkable fertility. It is seldom the case that the valley 

 sides are steep, like the bluffs of the Missouri river flood- 

 plain, although they are composed of the same material that 

 those are; but when we approach the point where the united 

 valley joins that of the great river, we begin to see the 

 abrupt and peculiar outline of the bluffs so characteristic 

 of the valley-sides of the Missouri river. 



Boyer river, until it enters the flood-plain of the Missouri 

 river, runs almost, if not quite its entire course, through the 

 region, the surface of which is occupied by the Bluff Deposit; 

 but like all others of the principal streams that run through 

 this deposit, it has cut its valley out of, and entirely through 

 it along almost its whole length. In consequence of this, 

 some pebbles and sand are usually to be found in its. imme- 

 diate bed, but nothing except the fine material of the Bluff 

 Deposit is elsewhere to be seen. This prevails so fully that 



