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The Journals of Lewis & Clark: Lewis, September 20, 1804

Lewis, September 20, 1804

Septr. 20th on the lard. shore at the commencement of the big bend observed a clift of black porus rock which resembled Lava tho on a closer examination I believe it to be calcarious and an imperfect species of the French burr- preserved a specemine, it is a brownish white, or black or yellowish brown-

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