It is nearly 500 years since the great raid of the nephew of Hung Wu, founder of the Ming Dynasty, from the southern capital of China, to what is now known as Peking, then called the state of Yen. The celebrated raider is popularly believed to have destroyed the lives of all those whom he met, and to have reduced to an uninhabited desert the whole region from the Yang-tzŭ River to Peking. This is described as "Yen Wang's sweeping the North." After this ambitious youth had dispossessed his nephew, who was the rightful heir to the throne, he took the title of Yung Lo, which became a famous name in Chinese history. To repair the ravages which he had made, compulsory emigration was established from southern Shan-hsi and from eastern Shan-tung. Tradition reports that vast masses of people were collected in the city of Hung-tung Hsien in southern Shan-hsi, and thence distributed over the uncultivated wastes made by war. Certain it is that throughout great regions of the plain of northern China, the inhabitants have no other knowledge of their origin than that they came from that city. It is a curious phenomenon that so practical a people as the Chinese, and one having so instinctive a sense of the points of the compass that they speak of a pain in "the east side" of the stomach, are indifferent to regularity of form in their towns. Every Chinese city seems to lie four square, but perhaps it is not too much to say that no Chinese city really does so lie. On the contrary a city wall is always found to have certain deliberate curves and irregularities which are designed for geomantic purposes. In other words they bring good luck, or they keep off bad luck, and are representations of the mysterious science of _fêng-shui_ or geomancy. It is for this reason that city gates must either not be opposite one another, or if they are so, some obstruction must intervene to prevent evil spirits from making a clean sweep of everything.