[17] Newport News, Va.: The Mariners" Museum, 1937, p. 23.

[18] Indianapolis, Ind.: Bobbs Merrill, 1932, p. 291.

[19] HENRY WILLIAM EDWARD, _The Double Bottom or Twin Hulled Ship of Sir William Petty_ (Oxford: The Roxburghe Club, 1931).

[20] Publication No. 5 (Newport News: The Mariners" Museum, 1939), p.

22.