It appeared, further, from his evidence, that Mr. Porter was for a complete abrogation of the English Navigation Laws, without any reservations as to reciprocity, and that, from the general conviction that these restrictive laws were rather injurious than beneficial to us, independently of the policy of other nations. [Sidenote: Their extreme views not conclusive to the Committee.] It cannot, however, be said that, in 1847, the repeal party had succeeded in convincing the majority of even the Committee of the soundness of their opinions. The shipowners, as a body, endeavoured to controvert, and with considerable show of success for the time, the theories propounded by the Free-trade party, so strenuously supported by the officers of the Board of Trade. The cold imperturbable evidence of Mr. (now Sir) John Shaw Lefevre, who was intimately connected with the Free-trade party, contrasted strikingly with the impetuosity of such men as Mr. Macgregor, and even with the testimony of Mr. Porter. [Sidenote: Evidence adduced by the shipowners.] The shipowners, on the other hand, put forward their most practical and intelligent witnesses[62] to prove that the repeal of the Navigation Laws would cause an immediate depreciation of thirty per cent. in the value of their property, and of shipping, generally, throughout the United Kingdom; that, if the British shipowner were deprived of his privileges, already greatly curtailed by the system of reciprocity, it would be decidedly to his advantage to invest his capital in foreign ships, and to navigate them by foreign seamen: Englishmen, they alleged, would own, in conjunction with foreigners (if possible), foreign ships, in order to secure the privileges still attaching to foreign flags, since British ships would still be excluded from many foreign ports, even though the Navigation Laws were abrogated. It was shown, as they conceived incontestably, that a ship could be built at Dantzig at a much less cost than in England,[63] and that, if the foreign trade were thrown open without restriction, no one would think of building British ships; the result being, that a great number of persons dependent on shipping—shipwrights and others—must be thrown out of employment, with great general distress ensuing. The difficulty of manning the Royal Navy, under such untoward circumstances (a standard argument), was, of course, dwelt on with great force as an unmitigated national evil. It was further urged, that the relaxation of the laws, so far as to allow Asiatic and African produce to be admitted to Great Britain for home consumption from ports in Europe, in all bottoms, must deprive the British shipowner of his most valuable privilege, and destroy the very essence of the ancient law. [Sidenote: Ships built more cheaply abroad.]