A long whip: hence the teamster who wields it.

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1859.  Gentile and Mormon, bull whacker and Pike’s Peaker, all seem to mingle freely.—Alta California, Aug. 17.

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1861.  Five yoke of oxen is the motive power for each wagon [going to Pike’s Peak], and these are urged forward by a ‘bull-whacker,’ armed with a whip, carrying a lash from six to twelve feet in length, which makes its mark wherever it falls.—Knick. Mag., lviii. 117 (Aug.).

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1878.  Numbers of white “bull-whackers,” sunburnt, healthy, and jolly, carrying with them constantly their murderous whips, which look as if one heavy stroke with them would flay a cow’s back.—J. H. Beadle, ‘Western Wilds,’ p. 407.

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1888.  I employed old-time bull-whackers, who had done nothing but scare about buffaloes all their life.—San Francisco Examiner, Feb. 23 (Farmer).

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1888.  There is no sound like the snap of the lash of a “bull-whacker,” as they are called, and perhaps brighter women than I am might have been taken in by it, and thought it a pistol-shot.—Mrs. Custer, ‘Tenting on the Plains,’ p. 229.

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1890.  We employed a Pike county bullwhacker, who agreed to deliver us and our effects in Hangtown for a certain consideration, payment invariably in advance.—Haskins, ‘Argonauts of California,’ p. 52.

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