"Geological Map of Isle Royale Lake Superior, Michigan", U.S. Government
Period: 1847 (dated)
Publication: Report on the Geological and Mineralogical Survey…
Color: Hand Color
24.7 x 17.5 inches
62.7 x 44.5 cm
This early geological map locates Sandstone, Conglomerate and "Trap: Basalt, Porphyry" formations with three different colors. Legend keys Mines, Abandoned Mines, Mineral Land Supposed to Contain Copper, Furnace, and more. The report noted is also known as Exec. Doc. No. 5, 31st Congress, 1st Session. The survey and map is by geologists J.W. Foster and J.D. Whitney with assistance from S.W. Hill and W.S. Chlatter.
References: Karpinski (MI) #764; Marcou & Marcou #363.
Folding, as issued. A little toning or light foxing mostly at upper margin and in upper left corner, else a clean and bright example.