The successful smelting and refining of the magnetic sand or titaniferrous iron ore is one of the open problem to be solved in the field of chemical and metallurgical engineering of Japan. For several years, the auther has devoted himself to the researches of the treatment and the utilization of the magnetic sand which contains about 15% of titanic oxide, in the laboratory of the Mitsubishi Iron and steel CO. under the auspice of the Imperial goverment.
In this short report, some of the results of the electric reduction and refining of the magnetic sand. is summarized.
At first the author explains, why he adopted the method of electric smelting and refining, and compared it to both blast furnace and spongy iron process from Technical point of view. Formerly, it was generally believed that the slag containing high percentage of TiO₂ is quite difficult to fuse or nonfusible at moderate temperatures. But he claims that the slags of high TiO₂ can easily be smelted at moderately low temperatures, say 1, 250-1, 350°C at the certain compositions of the slag.
The special compositions of the slag, which he named as the "Eutectic slag" are as follows; -TiO₂ 15-20%, SiO₂ 36-44%, CuO 25-32%, and Al₂O₃ and MgO under 10% respectively. It has a good fusibility and fluidity at 1, 280-1, 350°C and comes out of the furnace quite smoothly.
By preparing the composition of charge so as to make the Eutectic slag, he got both kinds of Pig iron-gray and white from electric furnace and gave the explanations of the mechanisms and factors of the formation of both iron.
Afterward, he applied the results of the researches in the laboratory to 300 K.W. 3 phase electric furnace (open type furnace) and 200 K.W. 3 phase furnace (Enclosed type furnace capable of utilizing the exhaust gas.) and confirmed the practical industrial values of the continumse systematic working, i.e. Smelting from magnetic sand to pig iron as intermediate product and from the pig iron to steel Ingot as end product.
The results of authors studies of wet method of treating magnetic sand and the design for determining the prencipal dimmensions of electric furnaces for smelting purpose are given in another publications.

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Casting the special cast iron that contained aluminium has generally been considered as a difficult operation. And hitherto this difficulty has been conceived to some contributions of its great tendency of slag-formation. The present author's attention has been directed to this tendency, and thermodynamical considerations have been undertaken to determine whether this difficulty only depends on this tendency or not, by treating the principal chemical reactions that may induce slag-formation when the special cast iron has been cast at 1, 400°C.
Also a similar consideration has been undertaken for an ordinary cast iron at the same conditions. Then free energies thus gained thermodynamically for these two kinds of cast iron have been compared. And the author has arrived at the conclusion that the difficulty as above described may not directly depend on its great tendency of slag-formation, but rather, on the chemical or physical properties of Al₂O₃ has been cast at 1, 400°C.
Also a similar consideration has been undertaken for an ordinary cast iron at the same conditions. Then free energies thus gained thermodynamically for these two kinds of cast iron have been compared. And the author has arrived at the conclusion that the difficulty as above described may not directly depend on its great tendency of slag-formation, but rather, on the chemical or phsical properties of Al₂O₃

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The effect of forging ratio on the mechanical properties of forged steels was examined on a carbon steel and two alloy steels both in annealed and heat-treated conditions. In the result we see that the tensile strength and the elastic limit show a slight decrease with the increase of forging ratio in the case of carbon steel and Ni-Cr steel, while in high Cr steel they are, on the contrary, increased as the forging ratio rises. Brinell's hardness also shows the same tendency as the tensile strength. The elongation and the contraction of area are markedly increased at the first step of reduction and attain their stational values at the forging ratio 1/4. The impact resistance and the number of repeated impact are found to reach their stational values at the forging ratio higher than 1/8. It has been considered that the forging effect in a steel billet is greater at its center than the surface; in the present investigation we confirmed the fact experimentally, and further made some mechanical tests to show the gradual change of the mechanical properties, from surface to center, in a forged billet

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The author confirms the existence of atomic hydrogen in iron nitride:
(1) By tbe presence of hydrogen when heating iron nitride aboce 43°C. at which iron nitride is found to decompose slowly.
(2) By the measurement of the single potential of iron nitride in the normal fargeus sulphate solution.
(3) By the oxidation of atomic hydrogen due to oxygen in the water in which iron nitride is immersed.
(4) By the transformation of potassium ferricyanide into potassium ferrocyanide by atomic hydrogen occluded in iron nitride.
By measuring the single potential of nitrided iron, he observed the change of compact iron into porous iron by nitriding.
The influence of light on the single potential of iron nitride was tested and it was found that light produces no marked photo-chemical effect upon it.

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