122 Featherstonhaugh's Geological Report. 



but the sky. At times the water was so shallow it was with 

 difficulty the canoe could be forced through it. Often it was 

 necessary to trust altogether to the compass, and the immediate 

 approach to Fort Winnebago was so tortuous, the channel so 

 often turned back upon itself, that the compass was quite use- 

 less. Whatever the direction, the country is covered with 

 these tall plants, and the grasses on the land, when you suc- 

 ceed in getting there, are so rank (now that the buffalo has 

 left this part of the country) that it is difficult to advance. It 

 is in fact the summit level of this part of the country, the Fox 

 river draining it towards the north, and Rock river and the 

 Wisconsin draining it towards the south. Before the retreat 

 of the waters, which has been before spoken of, which perhaps 

 was contemporaneous with the disintegration of the sandstone, 

 these extensive rice-swamps have been lakes, and it is only 

 since their subsidence that the zizania has begun to grow. 



In the neighborhood of Fort Winnebago the country begins 

 to rise, and the beds of carboniferous limestone observed in 

 Lower Fox river, are overlain by beds of quartzose sandstone, 

 having occasional siliceo-calcareous seams amongst them. 

 The sandstone beds are horizontal, disintegrate easily, and 

 are often variegated in color, having red, orange, and dark 

 tints. I was taken to a locality in the neighborhood of the 

 fort where this stone had been quarried, and became imme- 

 diately aware that I was in the vicinity of a galeniferous dis- 

 trict, for I was well acquainted with the analogous formation 

 in the State of Missouri, and which is spoken of in my report 

 of last year.* 



From Fort Winnebago there is a portage to the Wisconsin 

 river of about two thousand five hundred yards. This is a dead 

 flat of black mud and sand, occasionally overflowed so as to 

 admit of canoes passing to Fox river, and from which the 

 waters have retreated. The Wisconsin is an ample stream, 



* Page 43. 



