Equivalent to “over the left.” Halliwell has “in a horn when the devil’s blind.”

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1840.  

        A jury case, too, with lawyers for trimmings,
  And a plaintiff who looked so forlorn;
For his battered arm he bore in a sling,
  But I spec it was all in a horn.
Daily Pennant, St. Louis, Sept. 9.    

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1858.  

        That is how I was converted; (was it, think you, in a horn?)
Thus the sublime truths came to me, doctrines that I ’d viewed with scorn.
‘My Spiritual Experience,’ Knick Mag., li. 145 (Feb.).    

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1858.  I have mentioned before the innumerable comforts—in a horn—of the old White Sulphur Springs.—Evening Star (Washington), Aug. 26 (Bartlett).

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1866.  Methinks I see them, as in a horn, crowding the road, and swimming the rivers, and climbing the mountains, exclaiming with majestic fury—

        “We come, we come—ye have called us long—
We come o’er the mountings—in a horn.”
C. H. Smith, ‘Bill Arp,’ p. 56.    

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