A large hat. See quotation.

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1836.  As we were about mounting, the conjurer’s big white Vicksburger was unaccountably missing, and nowhere to be found. He was not altogether pleased with the liberty that had been taken with him, and after searching some time in vain, he tied a handkerchief around his head, sprung upon his horse, and rode off with more gravity than usual.—‘Col. Crockett in Texas,’ p. 137. (On p. 144, the conjurer is “cocking his large Vicksburger fiercely on his head.”)

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