Native Copper of Lake Superior, &c. 203 
leagues to the west of the Ontonagon river. It is overlay~ 
ed in other parts by a stratum of grey pais resembling 
certain varieties of grauwacke, of uncommon thickness, 
which appears in various promontories alon: the shore, and 
at the distance of ninety miles from Point Iroquois, consti- 
tutes a lofty perpendicular wall upon the water’s edge cal- 
led the Pictured Rocks, which is one of the most. com- 
manding objects in nature. So obvious a change in the 
geological character of the rock strata in passing — lake 
Huron to lake Superior, prepares us to expect a correspond- 
ing one, in the imbedded minerals, and other vente associa- 
tions,—an expectation which is realized during the first 
eighty leagues, in the discovery of red hematite, Sear 
opal, jasper, sardonyx, carnelion, agate, and 
first appearances of copper are seen on shee head of 
the portage across Keweena point, two hundred and seventy 
miles beyond the Sault de St. Marie, where the 
along the shore of the lake contain native copper dissemi- 
nated in particles varying in size from a grain of sand to e 
lump of two pounds weight. Many of the detached stones 
at this place are also coloured green by the carbonate of 
copper, and the rock strata in the vicinity exhibit traces . 
the sameore. These indications continue to the river 
tonagon, which has long been noted for the Marne 2 masses of 
native copper found upon its banks, and ab the contigu- 
ous country. This river (called Donagon o on OMellish’s Map) 
is one of the largest of thirty tributaries which flow into the 
lake between Point Iroquois and the Fond du Lac. It orig- 
inates in a district of mountainous country intermediate be- 
tween the Mississippi river and the lakes Huron and Superi- 
or, and after running in a northern direction for one a 
dred and twenty miles, enters the latter at the distance o 
fifty one miles band of Ar etaacner eames in | north latitud ae 
52! 2! ac 
is Seetrener by on 
Green Bay, and with 
lhataiataied communica 
dependently of that Cri Tose appear to unite 
the ordinary advantages of Tadinn villages in that region. 
