Railroad “sleepers” are usually called “ties” in the U.S., though the English word was long familiar.

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[1802.  In an advertisement for the building of a bridge over the Loyalhannah, the bidders are notified to furnish “the dimensions of their sleepers, planking, &c.”—Farmers’ Register, Greensburg, Pa., April 3.]

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[1818.  We are informed that the old piers [of the Springfield Bridge] remain, that the planks and sleepers were saved.—Boston Weekly Messenger, March 12.]

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[1852.  His camp he had before fortified; and now the planks were taken from the bridge over the creek, the sleepers greased and fortified by a tete-de-pont; and then going familiarly among his men, the Colonel prepared them for a bloody and desperate struggle.—C. H. Wiley, ‘Life in the South,’ p. 132.]

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[1852.  

        Eager politician,
  Closing up his peepers,
Runs off in a train
  Laid on heavy sleepers.
‘The Rhyme of the Dépôt,’ vi., Knick. Mag., xl. 315 (Oct.).] (Italics in the original.)    

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[1856.  There was quite a quantity of wheat that lodged on the beams or sleepers, and this was excellent wheat, but there was considerable dirt with it.—Orson Hyde at the Mormon Tabernacle: ‘Journal of Discourses,’ iv. 213.]

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1862.  The valley of the Kansas river … is supplied with timber unsurpassed in the West. This timber would furnish all the necessary cross-ties, trestle-work, &c.—Mr. W. M. Dunn of Indiana, House of Repr., April 17: Cong. Globe, p. 1702/1.

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