And from Lighter again. The publication date is 1826, but Lighter's biographical info suggest the singer might have learned this Sally Brown "sailors' chant" anytime between 1808 and then.

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Isaac Starr Clason, "Horace in New-York," 1826, p. 46: "The present Manager of the Chatham Garden Theatre, was formerly a Lieutenant in the British Navy. He was afterwards on the boards of the Norwich Company in England. He was principally applauded for singing a common sailors' chant in character, having a sort of 'Sally Brown, oh, ho,' chorus; and requiring the action of pulling a rope, spitting upon the hand, and the accompaniment of a horrid yell. In private life, both Mr. and Mrs. Wallack were much respected."

Clason's use of the word "chant" is almost as significant as "Sally Brown," "pulling a rope," and "a horrid yell." This could be the earliest clear reference to a "sea shanty as we know it," complete with Hugill-style "hitch"!
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