Sailing ships from Massachusetts first established the trade between American and China. Before 1842, the only port open to foreign trade was Canton in south China. Trade through Canton was dominated by tea, silk, and spices, which are cargoes of light weight and high value. Speed was an important factor, and the Yankee clippers were designed for the greatest possible speed under sail, delivering Chinese goods to waiting consumers in Europe. The Opium War between Britain and China in 1842 resulted in the Nanking Treaty, the first ever between China and a European power, and an end to China's policy of exclusion. Anxious to obtain trading privileges on a par with Britain's, Daniel Webster, then President Tyler's secretary of state, sent an envoy, Caleb Cushing, to negotiate that end. The result was the Treaty of Wanghia, signed on July 3, 1844, through which the principal American objectives were achieved. In 1850, the Taiping Rebellion broke out, under the leadership of a charismatic Christian leader Hong Xiuquan. Continuing until 1864, the rebellion may have involved the greatest number of men under arms of any 19th century military confrontation and was certainly among the deadliest, with total military and civilians deaths estimated at between twenty and thirty million. The resulting chaos made it difficult to enforce the provisions of the Treaty of Wanghia, and both Britain and France counseled an aggressive policy towards China. The United States declined, and instead instructed its envoy William B. Reed to work towards peaceful cooperation with France and Britain along while pursuing the following points: