filling a gap

[GEORGE THOMPSON]

        The cries the leadsmen taking soundings used, to inform a boat's
pilot of the depth of water under the boat, are well known, thanks to
Mark Twain.  It seems, however, that they are not well-documented.
The OED cites the same sources for "deep" and for "mark": the
earliest from 1769 and the next not until c1860.  The following
whimsy, from a letter to the editor complaining of two deep puddles
in Pearl St. near John St., fills that gap and also seems to give the
earliest American provenance.

        [The puddles are so deep that] . . . one might exclaim, as he wends
his way home, through the silent and watch-forsaken streets, towards
his cheerful lodgings, "by the deep nine," "by the mark ten."
        Commercial Advertiser, January 23, 1826, p. 2, col. 5

GAT