Meanwhile, within this period, the American wooden sailing-ships continued to be the glory of the seas, and the American clippers reached their highest development. The appearance of steamships on the North Atlantic and the Pacific had inspired the producers of the "wonderful American sailing-ships" to greater efforts for their perfection; and the clipper, surpassing all other types of sailers in size, sea-qualities, and speed, was the result of the intensified rivalry of canvas and steam.[GU] The American clipper-ship era fairly opened with the advent of the Collins Steamship Line.[GV] Between 1850 and 1855 clipper-ships were built for nearly every trade,[GW] and they were on every sea. Some of the first were employed in the transatlantic packet service. More became engaged particularly in the "booming" trade to California, in the long-voyage traffic to China and India.[GX] "When John Bull came floating into San Francisco, or Sydney, or Melbourne, he used to find Uncle Sam sitting carelessly, with his legs dangling over the wharf, smoking his pipe, with his cargo sold and his pockets full of money."[GY] The Crimean War, 1853-56, opened a new and prosperous market for American fast sailing-ships, as transports. To meet the demand American ship-yards produced in 1855 more tonnage than they had ever built before.[GZ] The sailing-ship interests strenuously opposed the subsidy system. They denounced it as class legislation unjustly favoring the few, and urged its abolishment.[HA] How strong this influence was in bringing about the change in policy is a mooted question. * * * * * No further move for fostering the American merchant marine with State aid directly or indirectly, was made till 1864. Then the steamship-subsidizing policy was revived, first with a proposition for the establishment of an American mail-line to Brazil. A subsidy of two hundred and fifty thousand dollars per year was proposed, one hundred and fifty thousand to be paid by the United States and one hundred thousand by the Brazilian Government. Congress endorsed the scheme. The act embodying it (May 28)[HB] authorized the postmaster-general to contract for a monthly service between the two countries, touching at St. Thomas, W.I., by first-class American sea-going steamships of not less than 2000 tons. The steamers were to be built under naval inspection, and to be subject to taking for war service. Bids were to be openly advertised for. The contract was to run for ten years. Thus was established the pioneer American line between Philadelphia and Rio de Janeiro, which continued from 1865 to 1876, and was then abandoned.