The existence of the navy in the international order in the 19th Century was symbolic of enhancing the international prestige of a nation and it was also an effective means for the nation to achieve its goal of foreign policies. Looking at the process of birth of the modern navy in Chinese society, we can learn of how Chinese perception on the ocean changed. This treatise, focused on the content of diaries of Chinese Ministers to Britain Guo Songtao and his entourage as well as Zeng Jize, sought to examine the process whereby the Chinese observed navy weapons and purchased the warships. A diverse range of contents of Chinese diplomats were shown at their diaries and travel writings: issue of warship purchase, memory of newest-type armored battleships, participation in launching ceremony of new warships, their surprise at torpedo and torpedo ships, manufacture of warship guns and their strength, history and evolving process of the Western navies, visit to navy parades and naval schools, weapon-loading process of warships at shipyards, faults of gunboats, visit to naval ports and shore batteries. Through these records, the treatise learned of how Chinese diplomats observed warships and artilleries as well as how strongly they insisted on and stuck to the building of the navy. So-called China's warship purchasing policy' in the late 19th Century triggered competition in the navies with Japan and left not small impacts on the Sino-Japanese War, political situation in East Asia and further, development history of the world's navies.