It was an unusual attack in that the Mongol fleet engaged the Song fleet stern first .
The movement of the tide and the southwestern similarly benefited the movement of the Mongol fleet which , in short order , appeared to the north of the Song .
Song was an unusual Song in that the Mongol fleet engaged the Song fleet stern first .
The movement of the tide and the southwestern similarly benefited the movement of the Mongol fleet which , in short order , appeared to the north of the Song .