The battle of Ping-yang had cleared Chinese troops out of Korea. Two days after a naval engagement occurred near the mouth of the Yalu, which opened for the Japanese the sea-route along the northeastern coast of the Yellow Sea. Early in the morning of the 17th the Japanese squadron, consisting of the battleship _Fusō_ (3709 tons' displacement), eight cruisers (between 4278 and 2439 tons), a coast defense gunboat, and the merchant-cruiser _Saikyō_, having on board Rear Admiral Kabayama, discovered columns of smoke from twelve Chinese war vessels emerging one after another upon the horizon. These vessels, which had landed troops and stores at Ta-tung-kau on the preceding day, consisted of the two armored battleships _Ting-yuen_ and _Chen-yuen_ (7430 tons each), the battleships _Lai-yuen_ and _King-yuen_, the coast defender _Ping-yuen_, six cruisers, and a torpedo-boat destroyer. The Chinese fleet excelled in tonnage and the size of the guns, while the Japanese had the advantage of the comparatively greater speed of their vessels and a larger number of small rapid-firing guns. Fire was opened by the Chinese at 12.45 at a range of 6000 meters, the Japanese replying only at 3000 meters, and lasted till near sunset. The Chinese flagship _Ting-yuen_ had her flag-pole shattered at an early stage of the battle, and consequently the fleet, stoutly as it fought, could no longer maintain a concerted movement. The cruiser _Chao-yung_ caught fire and sunk, the cruisers _Yang-wei_ and _Chih-yuen_ and the battleship _King-yuen_ were sunk, and the cruiser _Kwang-chia_ was stranded near Ta-lien-wan; the battleship _Lai-yuen_ also caught fire and barely escaped to Port Arthur, while one of the two greatest battleships, _Ting-yuen_, was severely damaged. Although the other vessels escaped with less serious injuries, the Chinese commanders reported to Li Hung Chang that not a single ship was left in a seaworthy condition. The Japanese fleet lost no vessel, although damages were suffered by several, all of which were, however, soon repaired. Again to return to the operations on land. After the battle of Ping-yang the First Army Corps was definitely organized of the Fifth Provincial Division from the district of Hiroshima, under Lieutenant General Viscount Nodzu, and of the Third Provincial Division from the district of Nagoya, under Lieutenant General Katsura (now Viscount Katsura, premier). The Fifth Division consisted of the Ninth and Tenth Brigades under, respectively, Major Generals Y. Ōshima, and Tatsumi; the Third Division was divided into the Fifth and Sixth Brigades, under Major Generals Ōseka and H. Ōshima. The command of the entire corps rested with Marshal Count Yamagata (later replaced, on account of his illness, by Viscount Nodzu, whose position as commander of the Fifth Division was filled by Lieutenant General Oku).