Geological map of Isle Royale, Lake Superior, Michigan / Made pursuant to the Act of Congress, approved, March 1st., 1847, by J.W. Foster & J.D. Whitney, U.S. geologists ; assisted by S.W. Hill & W.S. Chlatter.
From Michigan (In 5 layers) Depicts: 1849 Last modified about 2 years ago. Unrectified.
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