The author deals with the results of some experiments carried out on polished steel plates for deep-cupping which are adopted to motor-cars, furniture, electric apparatus, etc.
1) Relation between the working procedures and the properties of material.
For the material cold-rolled after pickling, there are three processes, i e., the direct use of the material as hot-rolled, the use of material worked after normalising or annealing. In comparing the three processes with respect to the working procedure and properties of material, the hot-rolled material is disadvantageous in its high hardness and difficulty in cold-rolling, but the operation is simple as a superior product with fine grains is obtainable by reducing the rate of cold rolling. Particularly, with a continuous-working equipment for the constant hot-rolling operation, the advantage is more conspicuous. The annealed material is not suitable for deep-cupping due to its coarse grains unless the rate of cold-rolling is made extremly high, the process being disadvantageous as it takes a considerable time for operation. The normalised material has properties between the first and the second one and the working heterogeneity accompanied with the hotrolling is well adjusted, the process being considered to be advantageous.
2) Relation between the strength of cold rolls and the properties of material.
The material rolled to 40% by passing it 6 times under the heavy reduction of a four high rolling mill and that rolled to 40% by passing it 48 times through a three high rolling mill were compared with respect to their properties after both having been annealed. The results indicate that the former is stronger with a larger elongation and is superior in the cupping
3) Comparison between the rimmed steel and the killed steel properties.
The steel sheets were experimentally made with three kinds of material, i. e., the dead-soft rimmed steel, the killed steel for black Sheet and the killed steel made by an electric furnace. In comparing the properties of the three materials, the killed steel is higher in the strength, and is inferior in the repeated bending but the Erichsen value and the cupping results are similar to the rimmed one.

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The influences of Al and Si on nitriding of steels were studied. The maximum hardness of nitrided cases is greatly influenced by the amount of Al, but scarcely by the amount of Si.
Nextly the properties of some different kinds of nitriding steel such as M_o-C_r-steel, Mo-Cr-Ni -steels etc. were studied, and the importance of such materials as high tensile steels are discussed. Also the mechanism of nitrogen case-hardening of steels is explained with the structural diagram of ternary system such as F_e-Al-N or F_e-C_r-N, which was proposed by one of the present authors several years ago.

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For the purpose of determining the chemico-thermodynamical values of FeO at a high temperature, which plays the most important rôle in the chemical reaction of the steelmaking process, a predetermined mixture of steam and hydrogen was passed over the surface of the liquid iron, heated by a high-frequency induction furnace at a temperature between 1, 545-1, 700°C, to establish the equilibrium:-
FeO(in Fe(l))+H₂ Fe(l)+H₂O(g)
And the equilibrium constant K=p_H2O/p_H2FeO% was measured, where the oxygen content was determined by the hydrogen-reduction method. From the results, the relation between the equilibrium constant and temperature is given as follows:
logK=6612/T-3.55……(1)
Using the equation (1), the equilibrium constants, determined at each temperature, are corrected to the values at the same temperature of 1, 600°C., which depend only on the temperature and are independent of the amount of FeO in liquid iron: i.c., FeO in this case behaves as an ideal solution.
From the equation (1),
Fe(l)+1/2O₂=FeO(% in Fe)
ΔF°=-29930-2.40T
Fe(l)+1/2O₂=FeO(l)
ΔF°=-61046+14.85T
are given. And the equilibrium constants of the following reaction,
FeO(in Fe(l))+CO Fe(l)+CO₂……(2)
are expressed as follow:
logp_CO2/p_COFeO%=7978/T-4.88
From the above, equilibrium constants at several temperatures were calculated in oder to compare with the experimental values.

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For a scientife control of the steel making process, it is indispensable to analyse a small quantity of gases in a finishing steel. The Orsat apparatus, which has been hitherto used for the purpose, has a fatal defect. In this apparatus the volume of gas is measured under a pressure of 1 atmosphere, so that the error incurred iu the volume-reading has a great influence upon the result.
The present authors prepared, therefore, a new analytical apparatus, in which a gas is measured under a reduced pressure and the effect of the error in the volume-reading becomes extremely small. In this patper, the apparatus is described and the results of the precise analyses of the gases, H₂O, CO₂, O₂, H₂, CO and N₂ in steels are discussed.

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In order to determine accurately gases contained in molten steel, the authors devised specially a sampling vessel made of transparent quartz, by means of which the gases in open-hearth steel were analysed.
The volume of the vessel is from 10 to 20cc. A thin copper plate is fitted at its end, and the vessel is made vacuous. When the vessel is immersed in molten steel, the copper is melted and the molten steel enters into the vessel, and simultaneously a portion of gases librates. The vessel is at once transfered to mercury bath so as to cool it, and the gases are analysed after being collected by a mercury pump, and further hydrogen in the sample is measured by a vacuum extraction apparatus at 800°C. Oxygen and nitrogen fixed in the sample are analysed by the vacuum fusion method.

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Les auteurs ont étudié le film mince du soufre orthorhombique au moyen des rayons cathodiques et ils ont trouvé que
(1) L'étude quantitative des diagrammes électroniques fournit les trois paramètres suivants: a=5·2Å; b=6.4Å; c=12·2Å, soit exactement les valeurs trouvées par Bragg.
(2) Il a été possible de suivre le passage progressif des diagrammes de réseau à 3 dimensions aux diagrammes de réseaux à 2 dimensions, grâce à la sublimation progressive des péllicules de soufre dans le vide. Nous avons obtenu les diagrammes correspondant aux plans que l'on observe le plue souvent pour des cristaux macroscopiques de soufre orthorhombique, soit les plans (100), (010), (011), (111).
(3) Sous l'influence de l'echauffement produit par le bambardement électronique ainsi que de la sublimation, il apparait parfois un brusque changement dans l' orientation du soufre étudié.

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