To measure.

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1750.  This divides into five branches, each equal to the large tree, some of them girting round about eight feet.—G. Hughes, ‘Barbadoes,’ p. 175. (N.E.D.)

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1817.  It is thought [the snake] will girt about three feet round the body, and his sting is about four feet in length.—Mass. Spy, Aug. 20.

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1823.  A hog, girting six feet four inches, and length nine feet, was shipped for New Orleans.—Id., Nov. 26.

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1858.  The tree “girts” eighteen and a half feet, and spreads over a hundred, and is a real beauty.—Holmes, ‘The Autocrat of the Breakfast-Table,’ chap. xii. (N.E.D.)

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