The new navigation acts : 3 Geo. IV. cc. 42, 43, 44, and 45 : with notes and observations : also the tables of custom-duties and drawbacks, list of articles which may be warehoused, and the bounties on silk manufactures and on salted provisions exported, the new regulations affecting custom house agents, and the new Ship Registry Act, 4 Geo. IV. c. 41 : with an index to the whole /