98 THE GEOLOGY OF MINNESOT A. 



[Hall, 1865. 



west, the conglomerate being particularly abundant on the Kettle river 



range. 



As corroborative of his own opinions, Mr. Taylor incorporates the 



views of Prof. James Hall who was, presumably, employed to make a 

 reconnoissance of the region in 1865. Prof. Hall is reported as saying that 

 the Taylor's Falls vein is a very distinct vein, quite equal, in what it shows, 

 to many of the best paying veins of lake Superior; and of the Kettle river 

 vein, that so far as can be seen of it, it is even more promising than the 

 one at Taylor's Falls, or the most promising that has been found in the 

 country. He regarded the whole St. Croix region as worthy of further 

 exploration for this metal.* 



In the same year Prof. Hall visited the southwestern part of the state, 

 his object being to ascertain the age of the coal that was then being 

 explored on the Waraju river. The next year an interesting paper was 

 published by him " On the geology of some portions of Minnesota from St. 

 Paul to the western part of the state." It is to be found in the Transactions 

 of the Philosophical Society of Philadelphia. The following points are 

 made in this paper: 



1. The Lower Magnesian and the Potsdam are seen in the bluffs of 

 the river to Mankato. 



2. A small portion of the St. Peter sandstone was seen at St. Peter, 

 still preserved above the Lower Magnesian. 



3. The rock at Pipestone he regards as Huronian. 



4. At Redwood falls, and at other places, he mentions the "steatitic 

 or glauconitic" beds resulting from the decomposition of the granite under 

 the Cretaceous. 



5. The limestone and green marls at New Ulm he regards Cretaceous. 



6. The red marls and sandstone underlying, he thinks " are not older 

 than the Triassic." 



7. He suggests the former probable continuity of the western and east- 

 ern Cretaceous areas with the southern prolongation of the same rocks up 

 the Mississippi valley. 



8. Suggests the parallelism of the red marls and ferruginous sandstones 



*A hasty statement has been made by Prof. R. D Irving in the Transactions of the American Institute of Mining 

 Engineers, Vol ViH, that this copper retrion had not been recognized by the Minnesota geologists, but was first brought 

 to light by himself. Dr. Shumard describes the same rocks, and Chas. Whittlesey says they are the "dying out in that 

 direction of the great Kewenaw range." 



