"Dog-VANE, (panon, Fr.) a small light vane, formed of a piece of packthread about two feet in length, upon which are fixed five or six thin slices of cork stuck full of light feathers. It is usually fastened to the top of a staff two yards high, which is placed on the top of the ship's side on the quarter-deck, in order to shew the direction of the wind to the helmsman, particularly in a dark night, or when the wind is extremely feeble."
"And there she steadied, racing through the sea and flinging a bow-wave so high to leeward that the sun sent back a double rainbow. Discreet cheering started forward and spread aft: everybody on the quarterdeck was grinning.
"'Watch your dog-vane,' said Jack to the helmsman. 'If you once let her be brought by the lee, you will never see Portsmouth Point again.'" --Patrick O'Brian, The Far Side of the World, 354
I just had to look up this one, c_b. Here's what I found on William Falconer's Dictionary of the Marine:
"Dog-VANE, (panon, Fr.) a small light vane, formed of a piece of packthread about two feet in length, upon which are fixed five or six thin slices of cork stuck full of light feathers. It is usually fastened to the top of a staff two yards high, which is placed on the top of the ship's side on the quarter-deck, in order to shew the direction of the wind to the helmsman, particularly in a dark night, or when the wind is extremely feeble."
"And there she steadied, racing through the sea and flinging a bow-wave so high to leeward that the sun sent back a double rainbow. Discreet cheering started forward and spread aft: everybody on the quarterdeck was grinning.
"'Watch your dog-vane,' said Jack to the helmsman. 'If you once let her be brought by the lee, you will never see Portsmouth Point again.'"
--Patrick O'Brian, The Far Side of the World, 354