A.- WTNCHELL — RES! LTS OF AJH III AN STUDIES. 



and moved certain distances into the body of the gneiss. We find them of 

 all sizes and of various thicknesses. At the points remotest from the schist 

 body the fragments may be a foot or three feet in Length, as presented edgewise 

 at the usual outcrop. At positions nearer the schist body the fragments are 

 larger, but generally without increased thickness. They become large flat 

 tables turned on edge, with thickness sometimes reduced to two or three 

 inches. Sometimes we find them broken and the pieces separated a few 

 inches. Next, we find their dimensions extending beyond the limits of prac- 

 ticable observation. They appear like split-off beds of the schists. In this 

 Btate their thickness diminishes, in many cases, to an inch or half an inch 

 or even a quarter of an inch. Thus we are compelled to contemplate the 

 mixed formation as a unit, produced by a system of alternating or inter- 

 rupted activities.* These included fragments retain, generally, a surprising 

 parallelism with the bedding of the body of schists. Even the short frag- 

 ments most remote from the schists generally lie in a conformable position. 

 The nearer sheets retain a rigid parallelism with the bedding of the body of 

 schists, and this is always coincident with the foliation of the gneiss, when 

 it e.\i-t-. The force which separated the schistic sheets could not have been 

 violent. The breakages which occurred could not have resulted from any 

 eruptive action. There may have been evenly distributed pressures, and 

 these may have floated apart the co-adapted fragments which were parted 

 by some adequate force. But they were not generally floated out of a com- 

 mon plane. The evidences of violent action are wanting. 



Exhibitions of phenomena such as above described are witnessed on every 

 band, but none surpass those found on the islands in Burntside lake. Re- 

 markable examples are see i White Iron lake. 1 The State Geologist of 



Minnesota remarks as follows of an occurrence on the Vermilion granitoid 



Area, at the western extremity of Vermilion lake: 



"Following the mica-schist bluffs west wardly, noting tin' line, conformable, and 

 increasing number of their sheets of granite, the facl suddenly flashes on the observer 



that the rock has 1> me changed ten reddish-gray gneiss, and n moment's further 



examination only i- net show it- further conformable transition to granite, thus 



making a conformable passage from en.- extreme to the other." 



Of another locality in the vicinity lie say-: 



"Showing tli" -Mm" kin. I of conformable interstratiflcation downward, demonstrat- 

 ing the existent I'u large mass of granite [gneiss] conformably interst ratified in 



mica schist and graduating into mica -<-lii-t above and below.' 



Of the junction of the gneiss and schisl at Whitefish bay of the Lake of 



tin- \V 1-, I >r. Lawson saj 



l in- junction it-"lf i- "\| 1 on tlii- shore, on il>" fi f a lew dill' presenting 



the appearance figured in the annexed diagram, there being apparently no sharply 



ill: .1-1. 



