A commercial treaty is a formal agreement between states for the purpose of establishing mutual rights and regulating conditions of trade. It is a bilateral act whereby definite arrangements are entered into by each contracting party towards the other—not mere concessions. Examples For example, the Methuen Treaty was a commercial treaty between Portugal and England. Another example, between the close of the Napoleonic Wars of 1815 and the year 1860, the tariff system of United Kingdom was changed from elaborate protection to practically complete free trade. An attempt had indeed been made in 1786 to modify the rigidly protective legislation of the 18th century. In that year Pitt concluded a commercial treaty with France, providing for large reductions of duties in both countries. But the treaty was swept away with the outbreak of the wars with France, and accordingly the old system was still in force in 1815. The first important step, and in some respects the decisive step, towards modifying it was taken in 1824, under the policy of William Huskisson. In that year, and again in 1825, great reductions were made in the duties on raw materials, especially on wool, raw silk, flax, and iron, while considerable reductions were also made in the duties on manufactured goods. The most sharply contested of the changes was in regard to silks, which had been completely prohibited, and were now admitted at a duty of 30 per cent. A considerable breach was thus made in the protective system; and some further changes in the same direction were made in the next decade, especially under Lord Althorp in 1833. But in the decade from 1830 to 1840 the Corn Laws were the chief subject of contention. The great increase in population since the middle of the 18th century had made England a corn-importing country, especially with the rapid growth of manufactures in the early years of the 19th century. The first systematic Corn Laws imposing duties on grain had been passed in 1773. From 1816 onwards a series of measures were passed, all designed to maintain the high price of grain. The Act of 1816 prohibited the importation of wheat when the price was less than 80 shillings a quarter (=$2.50 a bushel). In 1822 the prohibitive point was lowered to 70 shillings. In 1828 the sliding scale was introduced, under which the duty went up and down as the price of