On the Engines of the Motoraship “Monte Video Maru” By Y. Mitamura.
The paper describes the author's observations on the engines during his trip as a guarantee engineer on the vessel's maiden voyage to South America Sc back. The principal remarks made are : -the break down of the main engine piston packing ring, the erosion and damage given to the compressor H.P. valve, the stickiness of the bush to the main engine fuel-pump plunger, the rub-off of the cylinder liners and piston packing rings, the relation between the sparks from funnels and the fuel oils, the impurities in lubricating oil and its removal, the engine-room temperature and its ventilation.

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In 1918, experiments were carried out at the naval experimental tank, Tsukiji Tokyo, to investigate the effect of immersion upon the behavior of screw propellers. Series of elliptical three bladed model screw propellers were tested “in open” and in various depth of immersions. The scope and results of experiments are given in Table 1 in text and in Fig. 1.
It is observed that the correction percentages for thrust and efficiency due to change of immersion, within the limit of effective slip ratio of something 30% and under the cavitation limit, are very approximately common to all pitch ratios, developed area ratios and blade thickness fractions, and as indicated in Table 2.

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The resu'ts of model experiments of naked hull for the above case have been presented before this institution in 1920.
The present paper deals with the further investigation of the case for models with all appendages and also with propellers to find the effect of waves as well as propeller race of the leading model.
A short account of the apparatus used for “behind” experiment is given. The results obtained are :
(1) Wave making resistance of the following model is greatly affected by the distance, the maximum occurring at D/λ =0.85, 1.85, …, and the minimum at D/λ=1.35, 2.35, …, as in the case of naked hull. The propeller race of the leading model affects the resistance of the following model in similar way as waves produced by the leading one but in less significant degree.
(2) The number of revolutions of propeller, thrust deduction factor, &c. are affected by the speed as well as the distance of the models. The ratio of propeller revolutions of the two models seems to be represented by single curve for any speed and distance within the range experimented with, having maximum & minimum at 1.35 & 1.85 respectively.
(3) Finally it may be said that the following model is unstable to keep the distance constant when the model lies between the values of D/λ=1.351.85, and D/λ =2.352.85 and stable between D/λ =0.851.35 and D/λ=1.852.35.

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During the summer 1926, these experiments were carried out at the Teishin-sho laboratory at Tsukiji in Tokyo, and the following results were obtained : -
(1) Within the limits of our experimental work, the net frictional resistance could be generally expressed by the formula
R/ρFV²=a+l (ν/VD) ⁵
(2) The parameters a and b were found unaltered by the temperature of water, so long as the roughness of the surface was kept constant.
(3) As the surface was roughened, a increased and b decreased.

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An attempt to show an empirical standard for the longitudinal strength of the hull structure of steel steamers of ordinary type. The minimum thickness of the side plating and the maximum frame spacings for one-decked, two-decked and three-decked vessels for the side plating of this thickness, and also the average amount of the effective sectional area of the longitudinal members of the hull structure are dealt with in addition.

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Making a simple assumption for the mechanical viscosity the differential equations for the cases of flows of a fluid through pipe and over plane were solved. The coefficients of frictional resistance thus deduced agree very well with experimental results.

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Some points of importanc for the safe transportation of Japanese orange to South America (42 days). (1) Time and method of picking and gathering the fruits. (2) Handling of the fruits as a cargo. (3) Packing of the fruits. (4) Temperature and humidity of the cargo chambers. (5) Ventilation of the chambers.
The alteration of refrigerating-plant for the orange transportation (originally for the frozen meat) and the record of first voyage after the alteration on an average only 2 fruits out of 40 cases (each case contains 16-32 fruits) were found bad on delivery.

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This paper deals with tir following matters : - (1) “Tub-type Ships” is the name given to ships whose length and depth are small in comparison with the breadth. When they are in light condition, it is difficult to manoeuvre them, due to the poor steering quality. (2) Tests of cargo derricks must be done under heavier load than present practice, and the cargo gears such as hooks &c. must be made with greater factor of safety. The author makes several suggestions with respect to the topping lifts of derricks, the compressive stress produced in derricks, and the stays of masts. (3) Downton pumps have to be withdrawn from large vessels and pumps with oil engines to be adopted in place of them. (4) The author gives several remarks in regards to the method of fitting ringplates, bollards, fairleaders &c.

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These charts have been devised, as part of design charts, in view of doing away with the enormous amount of computation work in course of aeroplane design.
Chart I is a graphical representation of the logarithmic equations for the forces and the powers required and available in a steady climbing flight. It gives, readily yet accurately enough for preliminary stage of design, the horizontal speeds, the rates of climb, and the ceiling for all conceivable conditions and assumptions.
Chart II, supplementary to the first, is a logarithmic chart or Heinrich Kann's equation, which determines the time required to attain a certain altitude.
Chart III facilitates the calculation of the available power with various combinations of engipe and airscrew. The most appropriate engine-propeller unit can thus be selected from the accumulation of data in hand. The chart gives the power available for any altitude and also for any assumed attitude of flight.
Chart IV, by the parallel use of Chart III described above, enables one to obtain the required performance figures carried out to much higher degree of accuracy than are obtained by Chart I.

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