The carrying trade to the West Indies had been one of the most important branches of American industry. The men of New England were famous for seamanship, and better and cheaper ships could be built in the seaports of Massachusetts than anywhere in Great Britain. An oak vessel could be built at Gloucester or Salem for twenty-four dollars per ton; a ship of live-oak or American cedar cost not more than thirty-eight dollars per ton. On the other hand, fir vessels built on the Baltic cost thirty-five dollars per ton, and nowhere in England, France, or Holland could a ship be made of oak for less than fifty dollars per ton. Often the cost was as high as sixty dollars. It was not strange, therefore, that before the war more than one third of the tonnage afloat under the British flag was launched from American dock-yards. The war had violently deprived England of this enormous advantage, and now she sought to make the privation perpetual, in the delusive hope of confining British trade to British keels, and in the belief that it was the height of wisdom to impoverish the nation which she regarded as her best customer. In July, 1783, an order in council proclaimed that henceforth all trade between the United States and the British West Indies must be carried on in British-built ships, owned and navigated by British subjects. A serious blow was thus dealt not only at American shipping, but also at the interchange of commodities between the states and the islands, which was greatly hampered by this restriction. During the whole of the eighteenth century the West India sugar trade with the North American colonies and with Great Britain had been of immense value to all parties, and all had been seriously damaged by the curtailment of it due to the war. Now that the artificial state of things created by the war was to be perpetuated by legislation, the prospect of repairing the loss seemed indefinitely postponed. Moreover, even in trading directly with Great Britain, American ships were only allowed to bring in articles produced in the particular states of which their owners were citizens,--an enactment which seemed to add insult to injury, inasmuch as it directed especial attention to the want of union among the thirteen states. Great indignation was aroused in America, and reprisals were talked of, but efforts were first made to obtain a commercial treaty. [Sidenote: John Adams tries in vain to negotiate a commercial treaty.]