Letters from abroad brought by merchant ships (known as "ship letters") were by the Ordinance of 1657[682] and by the Act of 1660 made subject to postage on arrival in this country. Such letters were required to be given up to the postmaster at the port of arrival, who forwarded the letters to London, where they were charged with the proper amount of postage. No payment was made to the shipmaster in respect of letters handed over to the Post Office in this way, and no penalty was incurred if the letters were not so handed over. This part of the Act consequently remained a dead letter. The farmers of the Post Office saw, however, that it would be profitable to them to offer a small pecuniary inducement to the shipmasters, and accordingly offered to pay a penny for every letter brought by private ship and handed over by the shipmaster to the postmaster of the port of arrival.[683] As the farmers were able to charge the legal rate of inland postage on all such letters, there was a sufficient margin to leave a profit after payment of the penny. The regular ship letter fee, which was afterwards legalized, originated in this practice. Most of the ship letters came to the port of London, and the establishment of the penny post in 1680 had a serious effect on the proceeds of the ship letter money. If the letters were for delivery in London, they could be dropped into the penny post for delivery at a penny each, whereas if handed in to the General Post Office as ship letters they would be charged at the appropriate foreign rates, according to their place of origin. Thus, letters from Marseilles for delivery in London would be charged 1s. each, although the service actually performed by the Post Office was no greater than that performed for a penny in the penny post. The foreign rates, as applied to ship letters, were therefore for the most part a simple tax, and the use of the penny post was greatly resorted to.[684] The Postmasters-General protested continually against this fraud on the revenue; and in 1696, in order to put a stop to it, two officers were appointed whose duty it was to receive letters and packets from all "masters of ships and vessels, mariners, and passengers as shall be by them hereafter brought in any ships or vessels into the Port of London."[685] The payment of a penny a letter to the shipmasters was without legal sanction until the Act of 1711.[686] This Act revised the foreign rates, in general in an upward direction, the increase on the rates of 1660 varying from 1d. to 3d., and first established statutory rates for letters passing to or from the colonies. From London to or from the West Indies the rate was 18d. for a single letter, and to or from New York 12d. The rate to the West Indies was, in 1765, reduced to 1s. for a single letter, and this rate became in course of time the standard for all colonial letters.