 Complete the following phrase:  In the 1880s and early 1890s, the Beiyang Fleet conducted a routine of training exercises and cruises abroad, with emphasis placed on visits to Japan to intimidate the country. The latter resulted in the Nagasaki Incident in 1886 and contributed to a rise in hostility between the two countries that culminated in the First Sino-Japanese War in 1894. She saw action at the Battle of the Yalu River on 17 September, where the Japanese Combined Fleet sank much of the Beiyang Fleet, though both Zhenyuan and Dingyuan survived despite numerous hits. The survivors then retreated to Port Arthur for repairs, but after that city was threatened by the Japanese army, fled to Weihaiwei. While entering the port, Zhenyuan struck an uncharted rock and was badly damaged; she was used as a stationary artillery battery during the 