INTRODUCTION
they are of unique importance in connection with his account of the Corwin's landing on the island. The same considerations apply in a measure to Herald Island whose precipitous cliffs he was the first to scale as well as to sketch.
Since Muir's primary object in joining the Corwin expedition was to look for evidence of glaciation in the Arctic and subarctic regions, we have deemed it desirable to include in this volume the article in which he gathered up the results of his glacial studies and discoveries. It was published in 1884, with Captain C. L. Hooper's report, as Senate Executive Document No. 204 of the Forty-eighth Congress.
Both the Hooper report and the article on glaciation were elaborately illustrated from Muir's pencil sketches, though the fact that they were Muir's is nowhere stated. "The 'Glacier Article' arrived on the sixth," wrote Captain Hooper to Muir under date of February 7, 1884, "and was sent on its way rejoicing the same day. The Honorable Secretary [of the Treasury] assures me that he will see that the whole is printed without delay. Please accept my thanks for the article, which is very interesting. The sketches are very fine and will prove a valuable addition to the report. That of the large glacier from Mount Fairweather is particularly fine."
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