58 THE GEOLOGY OF MINNESOTA. 



[Featherstonhaugh, 1835. 



ment by the way of Green bay and the Wisconsin territory to the Coteau 

 des Prairies, an elevated ridge dividing the Missouri from the St. Peter's 

 river," printed by order of the Senate in 1836, and the other "A Canoe 

 Voyage up the Minnay Sotar," published in London in 1847. 



The latter is taken up largely with personal and journalistic details, 

 and the former with a statement of geological principles, as understood by 

 English geologists of that day. In his geological report proper Mr. Feath- 

 erstonhaugh ascribes the existence of lake Pepin to the entrance of the 

 Chippewa river, nearly at right angles to the Mississippi, damming up the 

 water above it ; mentions Castle rock as an instance of how " the mineral 

 level has been reduced," and gives an illustration of it, in which it appears 

 very much as it does at the present day; visited Fountain cave near St. Paul, 

 and describes it under the impression that it is that visited by Carver; speaks 

 of the " carboniferous limestone " at Fort Snelling, correcting Mr. Keating's 

 error in supposing fallen pieces of limestone from the top of the bluff were 

 in situ at the level of the river, and gives the following account of the falls 



of St. Anthony: 







FEATHERSTONHAUGH AT THE FALLS OF ST. ANTHONY. 



An island about 450 yards long divides the Mississippi into two parts at the falls of St. 

 Anthony, which have a very irregular outline, owing to the soft sandstone being washed out une- 

 qually in places, and the superincumbent strata of limestone falling down in large blocks ; these 

 are piled up in large quanities on the bed of the river immediately at the foot of the falls. That 

 part of the river on the north side of the island is about 220 yards wide. There is a very fine, 

 smooth section of the rocks here to the water, about ninety feet high. I should think the fall 

 would not average more than twenty feet. The immense slabs which have fallen from the lime- 

 stone 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 curvature, and measures about 450 yards 

 to the island ; the hight 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 hight. To a geologist, however, it is 

 exceedingly interesting, finding here the uninterrupted continuation, for one thousand miles, of 

 the carboniferous limestone with its characteristic fossils. At the south side of the falls 1 got 

 some exceedingly fine ones, including beautiful specimens of delphinula, bellerophon, nautilus, 

 euomphalus, &c. 



FEATHERSTONHAUGH ASCENDS THE MINNESOTA RIVER. 



Mr. Featherstonhaugh's geological notes on the Minnesota river may be 

 summarized somewhat as follows. Mentioning Carver's river, he says : 

 " Something short of fifty miles from the fort there is a short rapid with 



