A beginning of removal of the import and export duties, which had been laid for the purpose of encouraging or discouraging or otherwise influencing certain lines of production or trade, was made in a commercial treaty entered into by Pitt with France in 1786. The work was seriously taken up again in 1824 and 1825 by Mr. Huskisson, and in 1842 by Sir Robert Peel. In 1845 the duty was removed from four hundred and thirty articles, partly raw materials, partly manufactures. But the most serious struggle in the movement for free trade was that for the repeal of the corn laws. A new law had been passed at the close of the Napoleonic wars in 1815, by which the importation of wheat was forbidden so long as the prevailing price was not above ten shillings a bushel. This was in pursuance of the old traditional policy of encouraging the production of grain in order that England might be at least partially self-supporting, and was further justified on the ground that the landowners paid the great bulk of the taxes, which they could not do if the price of grain were allowed to be brought down by foreign competition. Nevertheless an active propaganda for the abolition of this law was begun by the formation of the "Anti-Corn Law League," in 1839. Richard Cobden became the president and the most famous representative of this society, which carried on an active agitation for some years. The chief interest in the abolition of the law would necessarily be taken by the manufacturing employers, the wages of whose employees could thus be made lower and more constant, but there were abundant other arguments against the laws, and their abandonment was entirely in conformity with the spirit of the age. At the close of 1845, therefore, Peel proposed their repeal, the matter was brought up in Parliament in the early months of 1846, and a sliding scale was adopted by which a slight temporary protection should continue until 1849, when any protective tariff on wheat was to cease altogether, though a nominal duty of about one and a half pence a bushel was still to be collected. This is known as the "adoption of free trade." It remains to be noted in this connection that "free trade in land" was an expression often used during the same period, and consisted in an effort marked by a long series of acts of Parliament and regulations of the courts to simplify the title to land, the processes of buying and selling it, and in other ways making its use and disposal as simple and uncontrolled by external regulation as was commerce or any form of industry.