A saber found on the Laiyuan. [Photo/China Daily]

"Historical documents show the fleet once applied to add 120-mm-caliber canons on the Laiyuan, but we didn't know whether the proposal was approved," Zhou explained. "Upon finding fuses on shells, we can confirm the ship was reinforced when preparing for the war."

Paying homage to the fallen sailors and calling for better protection of the shipwrecks in situ, Zhou said the shipwrecks would not be massively salvaged or moved onto land for exhibition.

"Remaining underwater, they can better remind us of history," he said.

China's systematic underwater research on the wrecks of the Beiyang Fleet began in 2014, mainly off the coast of Liaoning province where the Battle of the Yalu River was fought, and Weihai. Thanks to efforts over the last decade, the locations of all the fallen ships within Chinese waters have been confirmed.

"The building of the Beiyang Fleet was a crucial attempt of modernization in recent history," said Jiang Bo, a professor at the School of History and Culture at Shandong University. "The archaeological research can help clarify studies with refreshing ideas."

Zhou added that research on the wrecks will accelerate the adoption of new technologies in underwater archaeology.

The project has provided references for upcoming research involving other wrecks of modern warships within Chinese waters concerning the War of Resistance Against Japanese Aggression (1931-45), the Russo-Japanese War (1904-05), World War I and the Sino-French War (1883-85).

Wang Ru contributed to this story.