Warbird Information Exchange

Wakamiya was initially a Russian freighter ship named Lethington, built by Duncan in Port Glasgow, United Kingdom, laid down in 1900 and launched September 21, 1900.
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In 1913 she was transferred to the Imperial Japanese Navy and converted to a seaplane carrier, being completed on August 17, 1914. She was a 7,720-ton ship, with a complement of 234. She had two seaplanes on deck and two in reserve. They could be lowered onto the water with a crane, from where they would take off, and then retrieved from the water once their mission was completed.
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From September 5, 1914, she conducted the world's first naval-launched air raids from Kiaochow Bay off Tsingtao. Her seaplanes bombarded German-held land targets (communication centers and command centers) in the Tsingtao peninsula of Shandong province and ships in Qiaozhou Bay from September to November 6, 1914, during the Siege of Tsingtao.

British officers also serving in the Battle of Tsingtao commented on the operations of the Wakamiya:

"Daily reconnaissances, weather permitting, were made by the Japanese seaplanes, working from the seaplane mother ship. They continued to bring valuable information throughout the siege. The mother ship was fitted with a couple of derricks for hoisting them in and out. During these reconnaissances they were constantly fired at by the German guns mostly with shrapnel, but were never hit. The Japanese airmen usually carried bombs for dropping on the enemy positions."
—Report by Lieut. Commanders G.S.F. Nash and G. Gipps, HMS Triumph, 18th November 1914.