Abstract. A Device for the Simultaneous Recording of the Turning Circle, the Speed, etc. in the Turning Trial of a Ship. By S. Nitta. The author introduced a convenient arrangement of recording apparatus by combining those of the speed, the engine revolution, etc. with his modified track table, the detailed description of which was reported in the previous paper. (Jour. Jap. Soc. Nay. Arch, XLVII (1931), 185-194) In this arrangement, the speed, the engine revolution, the turning angle of the steering wheel, the helm angle, and the change of the ship's course are simultaneously transmitted to their respective recording pens by means of the electric transmitters from the S. A. L. log, the main shaft, the steering wheel, the rudder head, and the gyro-compass excopt in the case of the heeling angle, where the lever from the pendulum of the clinometer is used. Thus the systematic recording of the various cements in the turning trial can be obtained. The results of the experiments carried.out on board two warships in their turning trials and s, motor-launch in the large test basin at the Naval Technical Research Laboratory, Tokyo, are fully explained. The latter showed that the turning circles described by the author's apparatus agreed very well with those obtained by the " camera" method. The author is of the opinion that the