sentences:  The Russian delegation under Vice-Admiral Euphimy Vasil'evich Putiatin, was trapped in Shimoda at the end of 1854 when a tsunami caused by the Ansei Tokai earthquake destroyed their fleet.While a new ship was being constructed in nearby Heda, negotiations proceeded towards a treaty, and on February 7, 1855, the Russo-Japanese treaty of friendship was signed at Chōraku-ji by Putiatin as Russian Imperial Ambassador and Japanese representative Kawaji Toshiakira.The treaty comprised a trade agreement which opened three Japanese harbors (Hakodate, Nagasaki, and Shimoda) to Russia, one more than had been opened to the Americans.