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84 Copper and Silver of Kewenaw Point, Lake Superior. 
nation of this canal. The feasibility of constructing a ship canal 
from Lake Superior to the St. Mary’s river is perfectly obvious, 
only three locks of six feet each being required for the purpose. 
The only difficult part of the work will be in preparing a good 
entrance into the canal from the lake, where a breakwater will 
have to be made to protect the boats and the mouth of the canal. 
This work the United States government contemplates, and it is 
to be hoped will soon execute. There can be no better ground 
for a canal, for it will be cut wholly through soft sandstone, easily © 
wrought, but solid enough for substantial embankments, while 
the numerous erratic rocks near by, will furnish all the stone re- 
quired for building substantial locks. 
The sandstone on the lake shore at the head of this canal, dips 
to the S. W. 48° and runs N. W. and 8. E. Dr. Houghton has 
observed that the strata of this rock, wherever it comes on the 
lake coast, dip towards the lake, and so far as my observations 
have extended, I was able to confirm this remark. If it should 
prove to be the case around the entire lake, which has not yet 
been fully explored, it would lead to some interesting geological 
conclusions respecting the formation of this great basin ; for al- 
though there are many places where the elevation of trappean 
rocks has thrown up the sandstone strata at a bold angle, yet we 
should not be able to account for the elevation of so extensive a 
brim by local elevating forces; and since they act in directions 
deviating but little from a right line, or in gentle curves to the 
northwest, they would be inadequate to account for the phenom- 
ena, and we should have to regard the lake basin as a valley of 
depression. 
At Eagle Harbor the sandstones have evidently been disturbed by 
the intrusion of trap rocks, and dip N. N. W. 25°, but still towards 
the lake shore. The same dip was observed two or three miles in- 
land at Cat Harbor, and in every place where the sandstone was ob- 
served on the north side of Kewenaw Point. This would be ac- 
counted for by the direction of the great trappean ranges, which 
run in a general N. E. and 8. W. course, in the peninsula, with a 
gentle curve to the northwest. ‘The opposite or southeastern 
side of this point has not yet been examined, so far as I know, by 
any geologist, and it will be quite interesting to know the dip of 
the strata on that side of the trap rocks. If the dip should be to 
the northwest, then the trap dykes will be found to overlay the 
