Demand in Europe for Chinese goods such as silk, tea, and ceramics could only be met if European companies funneled their limited supplies of silver into China. In the late 1700s, the governments of Britain and France were deeply concerned about the imbalance of trade and the drain of silver. To meet the growing Chinese demand for opium, the British East India Company greatly expanded its production in Bengal. Since China's economy was essentially self-sufficient, the country had little need to import goods or raw materials from the Europeans, so the usual way of payment was through silver. The Daoguang Emperor, concerned both over the outflow of silver and the damage that opium smoking was causing to his subjects, ordered Lin Zexu to end the opium trade. Lin confiscated the stocks of opium without compensation in 1839, leading Britain to send a military expedition the following year.