The Young's moduli of nickel and iron, from room temperature down to -70°, have been investigated by the static deflection method. The amount of deflection of specimens is measured by observing the shift of interference fringes. The experimental results obtained are as follows: the Young's moduli of metallic nickel and iron vary linearly in the temperature range cited above and the anomalous change like that reported by Barbaron a few years ago is not recognized.

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Recently I have attempted some experiments to investigate the phenomena of metals under the action of sound wave, especially supersonics. The effects of supersonics to the solidification of metals are mainly described in this report. And the results obtained maybe summarized as follows; (1) Simple substances, such as Zn, Cd, which have considerably large grains in the ordinary method, have fairly small grains in this method of supersonics used. (2) In Al-Pb and Pb-Zn system, the uniform mixture of these elements can be produced by the emulsification under the action of supersonics. (3) It is remarkable fact that, in binary eutictiferous alloys, such as Pb-Sn, Pb-Sb, Coagulative phenomena take their appearances in addition to dispersive phenomena. Then I should like to add that the crucible used in these experiments is fused quartz one and the sound frequency used is 280 KC by piezo quartz generator, and 10 KC by magnetostriction.

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K-absorption spectra of electrodeposited cobalts with several thickness have been obtained and it is found that the secondary structures are similar to that of the other metals of face-centered cuibic lattice. The study on the similarity is also here made.

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The experiments on the electrolytic polishing of copper have been performed according to Jacquet's method, and furthermore the microstructural tests on the workhardened and the electrolytic deposited copper also have been carried out by the same method.
The results of the writer's experiments are summarized as follows; (1) The time of electrolysis has a remarkable effect on the relationship between the current density of anode and the voltage of cell. (2) The writer should like to recommend the following conditions to get the mirror-like surface of the copper. (i) Anode: Test piece as anode, vertically set parallel to cathode about 25mm apart. (ii) Cathode: Copper plate. (iii) Electrolyte: 50% aqueous solution of H₃PO₄ of specific gravity 1.75. (iv) Voltage of cell: 1.6 V. (v) Current density of anode: About 6A/dm², being regulated to keep voltage of cell to 1.6 V. (vi) Solution temperature: 25° (vii) Polishing time: 5_??_15min. (3) By the microscopic tests, the writer should like to point out that the lapping may have the effect to the depth from the surface about 0.06mm on the grain size and the hardness of the annealed copper. (4) And that the crystal grains of the electrolytic deposited copper is to be perfectly continuous with the base copper on the anodically polished surfaces, but to be discontinuous on the surfaces which are lapped or polished with emery paper, and be partially continuous on the surfaces which are etched by 10% aqueous solution of (NH)₂S₂O₈.

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Applying X-rays, we have examined the effects of the statical tensile stress and those of the repeated bending stress upon the crystalline configuration of annealed mild stcel, similarly as in the previous experiments carried out by the numerous investigators. The change of its lattice dimension due to these two kinds of the mechanical stresses is also studied from the back-reflected X-ray spectra taken in a particular way.
From the results of the present examination thus obtained, nothing could be found with respect to the effects of the statical tensile stress, but the continuous fragmentation of the micro-crystals and the formation of a fibrous-like structure, together with the gradual expansion of the crystal lattices, which had already been confirmed to occur:-that is, when the test piece made of this mild steel is stretched to break, the micro-crystals decreases their diameter continually from about 10^-2_??_10^-3cm up to 10^-5_??_10^-6cm and has the tendency to arrange themselves in a fibrous way, as it may be known from Photo. 3_??_4. While the crystal lattices increases their lattice constant, at least by the amount corresponding to the elongation percentage of the order 13×10^-4, as shown in the third column of Table 4. In addition to these, the effect of the repeated bending stress upon the crystalline configuration is also seen by Photo. 6_??_9, to remain essentially the same as those observe already by some investigators; no marked change is made for the most part of the fatiguing process, but at the moment of its fractuation, in the micro-crystals adjacent to the fractured end of the test piece, a sudden destruction is brought up to the size about 10^-4_??_10^-5cm in diameter.
It must be especially noticed, however, as a patent point of the consequence of the present examination, that the crystal lattice, which was innitially expanded by the amount corresponding to the elongation percentage of the order 4×10^-4, is confirmed to contract gradually up to that of the normal dimension of pure iron during the imposition of the repeated bending stress, which can be seen in the third column of Table 4. Such a contraction of the crystal lattice seems to be unexpectable at the first sight, but is anticipeted to offer an event that similar structual changes of the materials as are produced by the thermal treatments, can also be given rise to by some plastic flows.

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Studies on the electrolytic Co-deposition of magnesium-manganese alloy have been made for the purpose of producing with low price the magnesium alloys such as Elektron or A M 503, the corrosion-resisting alloy.
An electrolytic cell capable of producing magnesium about 40 kiro-gram per day is used. An intimate mixture of MgO₁ C and MnO₂ is charged to the molten MgCl₂-NaCl bath and is chlorinated by passing chlorine through the bath, and is afterwards electrolysed. As the results magnesium-manganese alloy containing manganese up to 1.5% has been obtained. Experiments on the production of the alloys containing higher percentage of manganese, say, 2.0_??_2.5% Mn will be reported next time.

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By carrying out the electrolysis in the buffer solutions with acetic acid-sodium acetate, acetic acid-ammonium acetate and formic acid-sodium formate, the pH ranges are determined in which manganese has been deposited perfectly on the anode. In the buffer solution of formic acid-sodium formate, the range is 2.0_??_4.0 and it is widest and suitable for the electrolysis. But the large excess of formic acid radicals makes the deposit imperfect and the relations between its quantities and pH are shown graphically. In the buffer solution of formic acid-sodium formate, the separation of manganese from the large quantities of nickel was tried and the manganese contained in the metallic nickel and nickel salts as impurity was determined.

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