52 R. Irving—Copper-bearing Rocks of Lake Superior. 
in every a manner, ic misplaced layers dipping in 
all directions, and in its immediate vicinity making a sort of 
brecciated mass of fapeinents of trap aud sandstone. This ap- 
pearance is presented along the hes aged side of a gorge, 
whose depth is more than a hundred feet, and is said by my 
assistant Mr. Sweet, who made all the observations in Douglas 
County, to be caused, beyond question, by no mere surface dis- 
placement, but by the general disturbed condition of the sand- 
stone. On passing down the gorge to the westward, the sand- 
stone layers become gradually less irregular, taking a prevailing 
northerly dip, until, 300 feet from the trap, they grade imper- 
ceptibly into the ordinary horizontal beds. Passing up the 
gorge to where the river falls over the trap, with a fall in all 
over 160 feet in height, the beds of melaphyre are found dipping 
southward at a low angle. On all of the other streams examined, 
the horizontal — ved layers of sandstone were found com- 
ing much closer tc the trap, but in all except the one already 
cited, showing ~ same peculiar disturbance, although on a 
smaller scale. 
hake in appearance, texture, Ke., more similarity to “the rocks 
of Illa in abinad County than to the more northerly beds of 
II hey appear, on the whole, to be rather more similar to 
an on the ine of the Brulé River. It is described as 
swampy and wee abe level, without many rock-exposures. 
the stream a a point marked 11 2 on the map). Still 
rose south the horizontal red sandstones are ony found (at 
points marked tv), and can be traced southward until they dis- 
Tantey. beneath the lighter-colored layers of the Mississippi 
pin of the rier Series, to draw attention to the fol- 
lowing points. The t belt of rocks of this series, which 
extends southwestwar ‘from Keweenaw Point to Long Lake in 
