Sir James Clark Ross had obtained a sounding of over 2,400 fathoms in 1839, but it was not until 1869, when H.M.S.是什么意思_Sir James Clark Ross had obtained a sounding of over 2,400 fathoms in 1839, but it was not until 1869, when H.M.S.在线翻译_英语_读音_用法_例句