Now that the Ming dynasty was firmly established the emperor turned his attention to Korea. He began by investing the king anew with the insignia of royalty and presenting him with a complete outfit of clothes of the style of the Ming dynasty. He also gave musical instruments and the Ming calendar. The important law was promulgated that after a man had passed the civil examinations in Koryŭ he should go to Nanking and there undergo further examination. The king received all the emperor’s gifts and commands with complacency and soon the Ming dress was adopted throughout by the official class and more gradually by the common people. It is the style of dress in vogue in Korea today, whereas the Chinese themselves adopted later the dress of their Manchu conquerors. In this respect the Koreans today are really more Chinese than the Chinese themselves. With the opening of 1371 Gen. Yi led an army across the Yalu and attacked Ol-ja Fortress. The whole territory between the Yalu and the Great Wall was at this time held by the Yŭ-jin people or by offshoots of the Mongol power. The Ming emperor had as yet made no attempt to take it and therefore this expedition of Koryŭ’s was not looked upon as an act of bad faith by China. Just before the attack on Ol-ja began, there came over to the Koryŭ forces a general who, formerly a Koryŭ citizen, had long been in the Mongol service. His name was Yi In-bok. Gen. Yi sent him to Song-do where the king elevated him to a high position. A bridge had been thrown across the Yalu and the army had crossed in safety, but a tremendous thunder storm threw the army into confusion, for they feared it was a warning voice from a deity who was angered by this invasion of trans-Yalu territory. With great presence of mind one of the leaders shouted that it was a good sign for it meant that the heavenly dragon was shaking things up a bit as a presage of their victory. Their fears were thus allayed and the attack upon the fortress was successful. Gen. Yi then led his forces toward the Liao Fortress but cautiously left all the camp baggage three days in the rear and advanced, with seven days rations in hand. The advance guard of 3000 reached the fortress and began the assault before the main body came up. When the garrison saw the full army approach they were in despair but their commander was determined to make a fight. As he stood on the wall and in person refused Gen. Yi’s terms it is said that the latter drew his bow and let fly an arrow which sped so true that it struck off the commander’s helmet, whereupon Gen. Yi shouted, “If you do not surrender I will hit your face next time.” The commander thereupon surrendered. So Gen. Yi took the place and having dismantled it and burned all the supplies, started on the return march. Provisions ran low, and it was found necessary to kill the beasts of burden. They were in some danger from the detachments of the enemy who hung upon their rear but they were kept