PHYSICAL GEOGRAPHY. 61 



River (a tributary of the Missouri), is a fine navigable stream 

 passing through a beautiful and luxuriant region, the follow- 

 ing account of which is given by Mr. Nicollet : 



" We reached the river Jacques, at a very celebrated spot, 

 called by the Sioux Otuhuoju — meaning, literally, the place 

 * where the oaks spring up,' but which I have designated on 

 my map as the ' Oakwood Settlement.' 



" The estimate which I have made of the distance between 

 this place and Fort Pierre is about 110 miles ; its actual ele- 

 vation above the sea is about 1,340 feet, and the descent from 

 the Coteau du Missouri to the river Jacques not less than 750 

 feet. The last fifty miles, by our route, belong to the east 

 slope of the Coteau du Missouri ; but, as we were obliged to 

 select our ground, allow^ing for this, the whole direct distance 

 is probably forty miles. In a similar way, estimating the 

 distance to the head of the Coteau des Prairies, which is 

 tliirty miles to the east, the basin of the river Jacques be- 

 tween the two coteaux, and in the latitude of Otohuoju,* may 

 be laid down as having a breadth of eighty miles, sloping 

 gradually down from an elevation of 700 to 750 feet. These 

 dimensions, of course, vary in the different parts of the valley; 

 but what I have said will convey some idea of the immense 

 prairie w^atered by the Tchansansan, w^hich has been deemed 

 by all travellers to those distant regions perhaps the most 

 beautiful within the territory of the United States. 



" I hazard, in conclusion of my remarks on the physical 

 geography of the valley just described, the suggestion that it 

 has been scooped out by some powerful denuding cause, and 

 that its original geological character w^as such as is now 

 observed in the Coteau du Missouri and the Coteau des 

 Prairies, by wdiich it is bounded. 



* About 45° 15'. 



