The Qianlong Emperor's Southern Inspection Tour, Scroll Four: The Confluence of the Huai and Yellow Rivers (Qianlong nanxun, juan si: Huang Huai jiaoliu). Artist: Xu Yang (Chinese, active ca. 1750-after 1776) and assistants. Culture: China. Dimensions: 27 1/8 x 431 1/4 in. (68.8 x 1096.17 cm). Date: dated 1770.This oversize scroll is the fourth in a set of twelve commissioned by the Qianlong Emperor to document his first tour of southern China, made in 1751. The scroll portrays Qianlong inspecting flood-control measures along the Yellow River. He stands beside the spillway that directs the clear, blue waters of the Huai River into the silt-laden Yellow River, diluting its sediment content and helping to flush the silt out to sea. The remainder of the scroll depicts various flood-prevention techniques, including double-sluice gates to reduce the force and flow of water into the Grand Canal, pounded-earth and stone-faced levees, and large bundles of sorghum used for repairing breaches i