Blinkers for horses.

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1808.  

          Long have they reign’d; till now the race at last
Shake off their manacles, their blinders cast.
Joel Barlow, ‘The Columbiad,’ x. 414. (N.E.D.)    

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1812.  [The cow], when she went away, had a board blinder.—Advt., Boston-Gazette, July 16.

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1848.  [Mr. Polk] was worked into the Presidency with Oregon and Texas on either side, as a horse is worked with blinds.—Mr. Thompson of Kentucky, House of Representatives, June 30: Cong. Globe, p. 820, Appendix.

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