Outlines of the Geology of Lake Superior, by 
Commander V1. W. Bayrietp, Royal Navy, 
Member of the Astronomical Society of Lon- 
don, and Honorary Member of the Literary 
and Historical Society of Quebec. 
i. Lake supertOR—Preliminary remarks.—2 Its 
geographical situation and magnitude.—3. Variation of the 
compass.—4. Depth and nature of its bottom.—5. Proofs 
that its waters have been highet.—6, No tides.—Local causes 
of the partial risings of its waters.—7. Whether its waters 
are still diminishing or not, uncertain.—S. Elevation of its 
surface above the sea.—9, Geological situation.—Extent of 
great chain of older rocks. Its basin and height of the 
sources of its rivers and of its hills.—10. Division of its 
rocks into orders. —11. Sienitic granite, its situation and 
extent.—12. Greenstone, common jasper, slates, and transi- 
tion limestone.—13. Trap or overlying rocks, amyg- 
daloid, porphyry, trap greenstone. Sketch illustrative of its 
occasional basaltic nature. Trap sienite, how distinguished 
from sienitic granite.—14. Old red sandstone, its extent, rests 
on granite. —How stratified. —Explanatory sketches and re- 
marks.—15, Reasons for naming the sandstone the old red, 
&c.—16. Traces of greywacke and remarks respecting the 
Greenstone.—17. Red rock of Neepigon bay,—18. lle Royal, 
native copper.—19. Michipicoten island.—20. Caribou island. 
21.—Islands of the twelve Apostles. —22, The great pros 
montory or peninsula of Keewawonan.—Situation of a vein 
of copper ore.—23, Remarks respecting the connexion and 
relative ages of the rock formations.—Boulders of shell 
limestone. —24, Alluvial deposits of the lake and its 
rivers, downs, alluvial deposits of the St. Louis, Raminis- 
tiqui-a, &c.—25. Synopsis of minerals. —26. Magnetic na- 
ture of the (rap rocks.—27. Concluding remarks, 
A Re 
