Free Trade
2 of the 7 encyclopedias on this shelf carry an entry for Free Trade. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
the term applied to national commerce when relieved from such interference as is intended to improve or otherwise influence it; that is, unrestricted by laws or tariffs, and not unduly stimulated by bounties. In all countries it was long held to be of importance to encourage native production and manufactures by excluding from their own markets, and from the colonial markets over which they had control, the competing produce and manufactures of other countries. On this theory the great body of British commercial legislation was founded till 1846, when the policy of free trade was introduced in grain, grain, and afterward gradually extended by the repeal of the navigation laws in 1849 and other great measures, till nearly all British commercial legislation had been brought into conforming with it. Free trade can hardly yet be said to have been adopted as a principle of commercial policy by any nation except Great Britain. As an economic principle, free trade is the direct opposite to the principle or system of protection, which maintains that a State can reach a high degree of material prosperity only by protecting its domestic industries from the competition of all similar foreign industries. To effect this, countries either prohibit the importation of foreign goods by direct legislation, or impose such duties as shall, by enhancing check the int the price, introduction of foreign goods. The advocates of what is called fair trade in Great Britain profess or even coma preference for universal mon free trade, but seeing that Great Britain is almost the sole free trade country in the world, they declare that a policy of reciprocity is required for the protection of British traders and manufacturers. See PROTECTION.
Aiton's Encyclopedia (1910)
the policy of allowing goods to be imported or exported without the payment of special taxes. It is opposed to the system of protection. By the Constitution of the United States the various states of the Union are forbidden to lay duties on goods imported from another state of the Union. The general government, however, is authorized to levy a tariff on articles imported from abroad. The leading free trade nation of the world is the United Kingdom of Great Britain and Ireland. Adam Smith, the Glasgow professor, advocated free trade in his Wealth of Nations published in 1775. Ricardo, a London banker whose works were extensively read, endeavored to convince the British public that the nation would be the gainer in the long run if the policy of free trade was adopted. William Pitt was a free trader. Richard Cobden and John Bright favored free trade. In 1869 Gladstone framed a free trade policy on a large scale. At the present time, 1910, the world at large is permitted to market its productions at British wharves as freely as though they were produced on British soil. Slight exceptions must be made to this statement, however. To discourage shipment abroad, an export duty is laid on coal. Imported tobacco, tea, rum, brandy, wine, coffee, currants, raisins, cocoa, sugar, and a few other articles pay an import duty, purely to provide the government a revenue, not for "protection." See Customs