The king’s teacher, Cho Kwang-jo, called “The Confucius of Korea,” told his master that Buddhism and sorcery were alike useless and urged him to do away with the headquarters of the diviners and sorcerers. It was done and the teacher was given the title of “Guardian of Public Morals.” We are told that this reign was the golden age of Korean morals. The people revolting from the excesses of the deposed king took on a puritan simplicity. Men and women walked on opposite sides of the street. If any article was dropped in the road no one would touch it, but would leave it for the owner to recover. No one had to lock his doors at night. When the wild Ya-in of the north ravaged the border and one advised that a force be sent disguised as laborers to chastise them, the king decided that it was beneath his dignity to have recourse to trickery, and so sent the troops openly. The important decennial examination called the Hyŭn-yang-gwa was now established. At this time white clothes were not largely worn. That custom did not come in till about 1800. Blue, red and black predominated. The king now established the custom of wearing very light blue at the time of ancestral worship. This reign saw some notable advances along certain lines. Bows were made which were shot by putting the feet against the bow and drawing the string with both hands. They were to be used by women in defending walls while the men might be away. A small powerful bow was made which shot metal arrows called “needle arrows.” They carried four times as far as the ordinary bow, and an arrow from one of them would penetrate three men. A kind of bomb was also invented. It was probably projected from a catapult of some kind. A spring trap was made whose arrow weighed a hundred and twenty pounds. In 1521 a Japanese So I-jön sent an envoy named Song-gong Pu-su-choa with a curious gift of three stones that resembled mirrors. The king, however, declined to accept them. The following year a Japanese named Teung Wŭn-jung went to the Chinese district of Yŭng-p’a and ravaged, and on his way home landed with his booty on the coast of Whang-hă Province in Korea. He was there captured by a Korean and his whole company were sent to China much to the delight of the Emperor. In 1524 P‘yŭng-yang was decimated by the cholera. It is said that there were 7700 deaths. The following year the envoy to Nanking, Yi Sun, brought back with him the first compass ever seen in Korea. In 1532 a royal concubine desired to have her son become king instead of the Crown Prince. In order to accomplish the destruction of the latter she took a dead rat, wrote his name on its belly and put it under the Prince’s room. This is a common way of attempting to do an enemy to death by witchery. She was discovered in the act and she and her son were put to death. Some three years later a great mock naval battle was fought on the river and the king went out and witnessed it.