Feather stonhaugWs Geological Report. 137 



have fallen from the limestone beds at the top are covered 

 with producta, mixed with spirifers and cardia. On the south 

 side of the river the line of the falls is a very irregular curva- 

 ture, and measures about four hundred and fifty yards to the 

 island ; the height of the fall does not appear so great on this 

 side, owing perhaps to the bed of the river being so much 

 choked up with the fallen* slabs. It is a wild, rocky scene, 

 but deficient in interest as a waterfall on account of its want 

 of height. To a geologist, however, it is exceedingly inter- 

 esting, finding here the uninterrupted continuation, for one 

 thousand miles, of the carboniferous limestone, with its char- 

 acteristic fossils. At the south side of the falls I got some 

 exceedingly fine ones, including beautiful specimens of del- 

 phinula, bellerophon, nautilus, euomphalus, &c. 



At Fort Snelling, the St. Peter's comes winding in from the 

 southwest, through an ample valley, the banks or bluffs of which 

 vary from one hundred to one hundred and fifty feet high. 

 The valley is about a mile and a half wide, and contains a 

 great deal of rich alluvial soil. On the right bank of the St. 

 Peter's, about a mile from the fort, is the head establishment 

 of the American Fur Company* for the trade with the Naco- 

 tah or Sioux Indians. 



The St. Peter's,f which remained forme now to explore, is 

 about one hundred and twenty-five yards wide at the nearest 

 point to the fort, looks as if whitish clay had been dissolved in it, 

 and runs with an extremely winding course, somewhat repre- 

 sented in the accompanying map, through the alluvial bottom, 

 with low prairies on each side, and fine wooded slopes in the 

 distance. The general direction of the river, as far as the 

 Makato or Blue-earth river, is about southwest ; from this point 



* From the gentlemen at the head of these establishments I received many 

 obliging- attentions ; and to Mr. Sibley, of this trading-post, 1 am indebted for 

 an excellent guide and interpreter, an intelligent and faithful half-breed, 

 called Milor, a man universally known in the Sioux country. 



t Called by the Nacotahs, Minify Sotor, or Turbid Water, in contradistinc- 

 tion to the Mississippi, which, coming from a siliceous country, is clear. 



