English: Drawing by William Alexander, draughtsman of the Macartney Embassy to China in 1793. A view of the Imperial, or Grand canal of China, which was extending from Canton to Peking, with river vessels passing through a sluice. Alexander noted that canals in China were very common and played the same role as roads through European countries. Other than transportation, they were also used for irrigation of the rice fields. Locks and sluices of various kinds were therefore very numerous: the print exhibits one designed as a bridge for the foot traffic; the building on the right serves to shelter those who are employed in raising the bridge. The vessel having the yellow or royal flag, was occupied by a part of the British Embassy. Image taken from The Costume of China, illustrated in forty-eight coloured engravings, published in London in 1805.