We measured the flicker value of officers engaged in coastal steamers and obtained the results as fallows ; 1. Dropping gradient of flicker value of them is more emnient in comparison with that of shore warkers. 2. Daily type of variation of flicker value is abnormal. 3. Flicker value drops eminent at the first day at sea and it likely to degenerate at the third day. 4. Shortage of sleep which comes from shift system of milion load of their quarter must be powerful reason of futigue.

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Usually we have considered the relative motions in the case that both motions are rectilinear or one is rectilinear and the other is circular. And the method taken so far has been Vector Calculation or the analysis using the time variable as the parametric representation. In this paper, relative motions against general curvilinear motions are universally considered dy using Cesaro's Natural Geometry. It is manifested that the relative motion which the circular motion works out against the rectilinear motion is Trochoidal motion and other several results are obtained. In the last part, we take up several exsamples indicating that the above method is very valid and uniform.

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It is important routine work to get ships position by observation of stars at sea and we have two difficult conditions when we observe several stars at the same time. First. We shall often mistake to identify a star owing to the scattered cloud in star sighting. Second. When the ship is heavily pitching and rolling on rough seas, it is hardly impossible to take down the reflection of the star by using sextant on the horizon without long experienced skillful technique, even if we recognize the stars. So, I thougt out the diagram to be composed of the following contents because we infer altitude and azimuth of the stars by D.R.P. and time (S.A.T. or S.M.T.) and take star-sight at the same time quickly and shortly. (1) Star-chart with dec. (2) Correction-table of S.H.A. at S.A.T. or S.M.T. (3) Diagram of altitude and azimuth. (4) Change of altitude in 4 minutes. (5) Conversion-table of time and degree. (0°〜90°).

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It is necessary to take water ballast in hold, etc, when ship sails at light condition. Taking water ballast, we must consider three problems as following ; 1. Virtual loss of GM [numerical formula] M: Righting mt, original. M_T: Free water tank's Mt. 2. Correction of phase diff, between ship and free water. [numerical formula] φ: phase diff. 3. Dynamical pressure at tank's wash plate, etc. [numerical formula] d: dist fr. Ship's C.G. to water ballast f(θ): Correction coeff. of anti-isochronism motion.

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In August, 1931, on the way from Uzina for Yokohama, the "No.14 Liverty", having no load, lost her screw by the racing off Tosa and began to drift under the weather of typhoon which was approaching. She was drifting eastwardly by the effect of Kuroshio in spite of east'ly wind. 4〜5 in force. After 2 days and 20h 18m, She was rescued by No.636 L.T. on the north-east'ly direction from Muroto-zaki. During her drifting, she was aided by No.18 and No.8 L.S.T., but it was no vain owing to the break of 5 inches Tug-rope. At that time, Tug-resistance was accounted 3.5 tons. From her drift by wind, wind direction and wind force, etc., current speed of Kuroshio is estimated 2.8 Knots.

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With a view to clarifying the empirical relations which stands between the turning motion of a given ship and the steerage, the authors have attemted the qualitative and quantitative analysis mainly in respects to the above title. In the first part, we have worked up a practical approximate formula according to which we can calculate an altering angle from original Co. to the desired Co. by the data easily determined on board ; in the second part, treated the qualitative problems in steering aspects which are mostly concerned with the handling of the ship, namely, the effect of the rudder in the initial stages of circular motion, the turning power of remaining after the helm is put amidship, the angle altered Course ; at last, made the relations clearer which lie among these handlings in which we have depended upon only intuitional and empirical capability. However, our treatment in each part has been considered merely from the manoeuverer's point of view. Therefore, although the results obtained may not be exactly mathematical, they are believed to be sufficient guides for practical use, as showed by the experiments of a training ship, Wakashio-Maru.

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The interpolation of the traverse table is not so simple as that of other tables. If we would seek an interpolation of the traverse table thoroughly, there are some Cases in which the purpose of the table is much reduced. But in the Calculation of navigation there are some Cases where we cannot neglect the interpolation of the traverse table. Nowadays the interpolation of the traverse table is looked for by means of propotional part, but when we search the course and distance with dep. and d.lat, it is very difficult to find them exactly. This paper is written to save this fault. In other words, when we look for the interpolation we sould depend upon the traverse table instead of the proportional part. Using the traverse table, we can easily seek an interpolation in full, and the exact Course and distance with dep. and d.lat.

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Ships nomally attain their greatest width in the middle and their greatest height at the ends, curving outward and downward from the ends towards the middle. The lower part of the cross Section of the galley was almost round in Shape and the long oars on both sides of the ship had to be made about twice as board as the hull below. Cannon, when first used, were fitted to galleys among the banks of rowers, such a type was clearly not suited for anything more than the needs of the Mediterranean. Vinice and Genoa had both built large carracks for their sea-trade, they were 'tumbled home'. because it was hard to get long lengths of timber for the purpose, and when two lengths had to be used the joints were a source of weakness and trouble. One of the main features of design was to settle the breadth and where the greatest breadth should be placed. The idea in Tudor days was to make the ship's shape below water conform to a cod's head and mackerel tail, then the fashion grew up to place the greatest transverse section of a ship midship bend (dead flat) some 40 per cent of the length on the gun deck from the bow. Contain details of the methods of drawing several typical midship bends.

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After the data, observed by a U.S. tanker on and off the gulf Stream, the auther had the value of mean velocity and standard deviation of that current. According to G.I. Taylor (1922), if we put Rζ as a correlation coefficient of the velocities between two times intervaled by ζ houres and assume Rζ=e^<-ζ/A>, then the standard deviation of the position of a particle transported by turbulent motion is expressed as formula (4). The error of the estimated position was calculated by the data above mentioned and shown is formula (7), and this seems to be rather good approximation with Prof. Samejima's value.

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The mandarine orange continiue their renewing faculty regardless of extraction from the tree, keeping their respiration and evaporation etc. even in a storehouse. We have no typical air condition for carrying of mandarine orange by sea, as to humidity, temperature and ventilation in a hold of ship. And then, there is no typical stowing method of mandarine orange in a ship by now. The question that I tried to research are what conditions of cold storage or hold are best to carry mandarine orange by sea.

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In taking sight when the celestial bodies are on the prime vertical, we can get a exact Longitude at this time and observed noon position most quickly in the conbination with "Sighting" of noon. For above reasons, we are often endevouring to take advantage of an opportunity to take sight at that time. So, I drew the graph, by which we can get "Hour Angle on the Prime Vertical" very easily and exactly and determine previously the time to take sight.

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