(i) Building canals : The French began by building canals and draining land in the Mekong delta to increase cultivation. The vast system of irrigation works canals and earthworks – built mainly with forced labour, increased rice production. (ii) Building of ports : To export the surplus production French built ports. These ports were used to export the rice to the international market. (iii) Increasing area under rice cultivation : The area under rice cultivation went up from 274,000 hectares in 1873 to 1.1 million hectares in 1900 and 2.2 million in 1930. Vietnam exported two-thirds of its rice production and by 1931 had become the third largest exporter of rice in the world. (iv) Construction of rail network : Construction of a trans-Indo-China rail network that would link the northern and southern parts of Vietnam and China was begun. This final link with Yunan in China was completed by 1910. The second line was also built, linking Vietnam to Siam (as Thailand was then called), via the Cambodian capital of Phnom Penh. (v) Establishing rubber estates : Many new rubber estates owned by the French businessmen were established. Indentured Vietnamese labour was widely used in the rubber plantations.