An attempt of measuring the rolling and heaving, and observing the shipping water of ship models on the regular short-crested waves was made to see the behaviours of the small crafts floating on the seaway, and the following results were obtained : (i) The rolling of a ship is easier on the short-crested waves than that experienced on the long-crested waves. (ii) On the top of the short-crested waves, the shorter the ship is the heavier the heaving becomes. (iii) The ship floating on the short-crested waves has more occasions of shipping water in spite of her reduced angles of roll.