E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Three Sheets in the Wind.
Unsteady from over-drinking, as a ship when its sheets are in the wind. The sail of a ship is fastened at one of the bottom corners by a rope called a tack; the other corner is left more or less free as the rope called a sheet is disposed; if quite free, the sheet is said to be in the wind, and the sail flaps and flutters without restraint. If all the three sails were so loosened, the ship would reel and stagger like a drunken man.
Captain Cuttle looking, candle in hand, at Bunsby more attentively, perceived that he was three sheets in the wind, or, in plain words, drunk.Dickens: Dombey and Son.