Yourig's modulus of elasticity E of single crystal of nickel was measured by a new microscopic method at room temperature. From E measured and the known value of compressibility of poly-crystal of nickel, the Voigt moduli were calculated. The results are as follow: s₁₁.10¹²=0.72₄, s₁₂10¹²=-0.26₇, s₄₄.10¹²=0.94₉: E_[111]: E_[100]=1.8₉, n_[100]=1/1.7₅. These values are all given in C. G. S. unit.

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A protective coating of some basic phosphates on a surface of magnesium alloys was prepared by the following process:-magnesium alloyed with manganese, zinc or iron was immersed in a mixed solution of a weak phosphoric acid and manganese, zinc or iron phosphate respectively and heated at 98_??_400°. When a coating of a basic phosphate was formed on the surface of specimen, the latter was washed in boiling water. The coating of these phosphates was more effective for magnesium alloys against corrosion of them by sodium chloride solution than that of magnesium phosphate formed by the process found by one of the writers 8 years ago, because the metallic phosphate, for example, manganese phosphate is firmly coated on manganese or on manganese oxide; this manganese remained on the surface of the specimen owing to the dissolution of magnesium or redeposited on the surface of the specimen. The specimens having the coating of metallic phosphate on their surface was then pressed and further coated with coal-tar by heating them in an autoclave. In this work many corrosion-resisting magnesium alloys were tested, and it was found that the coating of manganese phosphate was best, followed by zinc phosphate, iron phosphate in most cases being not so effective, except the case of PF(1) described below with the specimen in which the result was comparable as above two cases. The coating of manganese phosphate on the surface of alloys which contain manganese such as A, B AZG, L in Table 1 was more effective than other coatings, arid it was also confirmed that the manganese phosphate coating was fairly good if manganese content in alloy is more than 0.5%. Alloys containing aluminium 6_??_7% and a small quantity of other elements together with manganese were indifferent to form the coating, while in the case of alloys in which manganese content was below 0.2% and that of zinc 2_??_3%, the effect of the coatings formed by manganese and zinc phosphates were almost the same, for example, in the case of specimen C, manganese and aluminium contents were only 0.2% and 3.5% respectively and zinc was comparatively large; the coating of zinc phosphate was a little better or almost the same as manganese phosphate. In most cases the coating of iron phosphate was not so effective except the case of _??_ in which the baking of coal-tar in autoclave was carried out at 240° for 5 hours with a pressure of 70kg/cm². An improvement of baking with coal-tar in third process was made in the following manner:-in order to absorb sufficient coal-tar in the phosphate coating, first of all, the coated specimen was placed in vacuum vessel and the air absorbed was expelled and then placed it in burning tar in autoclave or a solvent of coal-tar was next made to absorb in the coating and put in coal-tar with high pressure in autoclave. The result was found to be more effective.

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The mechanism of the sintering of compressed metal powders, 90 parts of copper, 10 parts of tin and 2 parts, of graphite, was studied in detail by measuring density, hardness, electric resistance and expansion, and also by X-ray analysis and microscopical examination.
Theresult appeared to justify that:
(1) During the stages of the sintering process, one or more transient phases such as γ and other tin rich phases are produced and these powders, prepared by electrolysis, exclude the absorbed hydrogen gas. These two phenomena play a marked effect on the diffusion.
(2) The heating of about 3 hrs. at 650-700° is sufficient to cause complete diffusion of the compressed powders used in the investigation.
(3) The results obtained with graded particles showed that the interdiffusion taking place in a given time is greater, the smaller the size of the particle. This result harmonize with the observation of the inter-diffusion of copper and zinc by E. A. Owen and L. Pickup.

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The nature of the phenomena of K-absorption of X-ray by zinc was investigated and found that the phenomena consist of a main process, and an auxiliary one; the former is the electron transition from k-shell or the level, (1s)²¹S₀, to the opticallevel, (4s, 4p)¹P₁, ZnI, resulting so called K-absorption main edge; the latter, in nature, is Auger effect, giving rise to some breadth to the K-absorption edge, the emission lines, Kβ₂ and Kβ''', and to a fine structure of the main edge itself.
The nature of L-abdsrption of X-ray by zinc was also studied and found that the main process is the electron transition from L_{11, 111} to the optical level of the triplet system of ZnI, (4s, 6s) ³S₁, and the auxiliary one is the electron transitions between the levels, belonging to the triplet system of ZnI, K-and L_{11, 111} -absorptions in zinc oxide were also descrived. In these cases, the main processes are the same as in the cases of zinc respectively, but auxiliary ones consist of the electron transitions between atomic levels of oxygen of ZnO; this causes the shifting of the absorption edges.

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From the differences between the energy values of the crystal levels of zinc and that of the normal state of Zn-atom, the heat of sublimation of solid-Zn was calculated to be 0.099 Ryd per atom, which is in perfect agreement with the experimental value 0.098 Ryd.

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