The Mg-Cd system has a close-packed hexagonal lattice and possesses ordered structures for concentrations corresponding to Mg₃Cd, MgCd and MgCd₃. In general the close-packed hexagonal lattice (let the lattice constants of it be denoted by a and c) can be devided into four large hexagonal sublattices (lattice constants of them now become a'=2a and c=c) (Fig. 2). For ordered MgCd, two of these sublattices are occupied by Mg while the other two by Cd; and for the ordered Mg₃Cd three sublattices are occupied by Mg and the remaining one is occupied by Cd, for the ordered MgCd₃ the relation is just the reverse. We have measured through the order-disorder transformation of these alloys temperature dependencies of several physical properties, such as specific heat (C_p), expansion coefficient (β) and electrical resistivity (ρ). (Figs. 5-13) For Mg₃Cd alloy C_p-vs-temperature curve shows anomalous behavior similar to β-brass, while the, presence of latent heats has been confirmed for MgCd and MgCd₃ alloys. For Mg₃Cd and MgCd alloys, β-vs-temperature curves indicate the close parallelism to their C_p-vs-temperature curves. On the other hand, for MgCd₃ alloy, remarkable contraction is associated with its disordering, therefore, coefficient of thermal expansion tend to negative infinity at the Curie point, the ρ-vs-temperature curves for these alloys have characteristic from of the order-disorder transformation.
During the annealing of the previously quenched Mg₃Cd and MgCd alloys, their hardness decrease with time (Fig. 14). It is interesting to note that these highly ordered supperlattices possess hardness smaller than the random alloys of the same compositions, contrary to the Cu-Au, Fe-Ni and other cases. The results of these experiments are summarized in Table 1.

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In a previous paper (I), we reported on some physical propertis of the superlattices which correspond to Mg₃Cd, MgCd and MgCd₃. In this paper we shall present a general review of this Mg-Cd alloy system using the results of our investigations performedon about fourty specimes of various compositions.
The transition temperature-vs-composition curve is of a smooth parabolic form, having a maximum (ca. 250°) at the atomic ratio 1:1, but having.r.o maximum at 3:1 and 1:3 (Fig. 1). The specific heat-vs-temperaure curves and expansion coefficient-vs-temperature curves are represented in Figs. 2 and 3. Expansion coefficient-vs-composition curve has three maxima at the compositions 1:3, 1:1 and 3:1, for both ordered and disordered states (Fig. 4). The curves in Fig. 6 depict the electrical resistance measured at various temperature against alloy compositions. Below the Curie point, these curves show three minima in the neighbourhood of the compositions, Mg₃Cd, MgCd and MgCd₃, just as in the cases of the Cu-Au, Cu-Pt and other systems; while above the Curie point, the appearance of thee curves are very different from the other cases of ordinary superlatties; i.e. the alloys of compositions. rear MgCd have still lower resistance than those of other compositions. Fig. 7 represents graphically the hardness of these alloys as a function of compositions for both annealed and quenched states. It remains unexplained why the alloys near 40 atomic% Cd inaicate singularity in hardress-vs-composition and Curie point-vs-composition curves.
It is interesting to note that both specific heat-vs-temperature curves and expansion coefficient-vs-temperature curves cf an alloy corresponding to 44.5 atomic%, Cd, show three peaks (Fig. 10), and also that those of the alloys in region from about 60 to 68 atomic% Cd, have anomalous form, which appear to be originated from a superposition cf two peaks (Fig. 11). These phenomena may be explained by Shockley's theory on the Cu-Au alloy system.

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The above problem is treated by statistical mechanics under the corsideration that the amount of absorption of gas depends on the geometrical arrangement of gas particles in metal, if there is interaction among gas particles. The configuration of the arrangement of gas particles is introduced to the problem by the method of super-lattice formation in binary alloy. The result of calculation shows:
1. The effect of geometrical arrangement of gas particles to the amount of absorption appears when the interaction energy between gas particles is positive.
2. When the pressure of outer gas is constant, the influence of geometrical arrangement decreases the absorption amount as the temperature rises.
3. When temperature is constant, the influence of arrangement increases the absorption amount when the absorped amount is small, and decreases as the amount becomes large.
4 The experiment of the activated absorption of O₂ by Ag suggests the existence of such effect of the geometrical arrangement of gas patticles in metals.

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With about sixty, annealed, nickel-cobaelt alloys covering the whole composition range, magnetization curves for magnetic fields up to 900 oersteds were measured ballistically at ordinary temperatures. It is shown that magnetization curves have the three types corresponding to different structures involved in this alloy system, that is, γ (face-centered cubic) and ε (hexagonal close-packed) solid solutions and the mixture of these phases. Magnetization curves of γ-phase alloys show high susceptibilities, and saturate at relatively low fields (atmost 700 Oe). The magnetization of an alloy containing about 3 or 10 percent cobalt was found to saturate at the lowest field (about 30 Oe). ε-phase alloys have low suscetibilities and high saturation fields, and two-phase alloys show behaviors intermediate between γ-phase and ε-phase alloys.
The magnetization for constant magnetic field and the initial and the maximum magnetic susceptibility vs. composition curves show discontinuitic at 68 and 77 percent cobalt. These two compositions were shown to be the boundaries of the two-phase range, contrary to _??_ prevailing opinion that the range was quite narrow near 70 percent cobalt.
The relation between the saturation magnetization and composition of γ-phase alloys was found to be well expressed by two straight lines of slightly different slopes, which connected at the middle of the range. The straight line for high cobalt contents may, practically, be extended up to pure cobalt.
Both initial and maximum magnetic susceptibilities show three sharp peaks in the compostion range below about 30 percent cobalt. Provided that the first, comparatively low, peak is neglected, this mode of variation is quite similar to that of the contribution of the continuous rotation of spontaneous magnetization to the initial susceptibility. This means that the said contribution to the initial susceptibility may bs superior to, other contributions in materials of low anisotropy constant.

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Young's modui of elasticity E of three single crystals of cobalt prepared by the method of slow solidification were measured by a new microscopic method at room temperature. From E measured and the known value of compressibility of a poly crystal of cobalt, the Voigt moduli were calculated. The results are as follows S₁₁=0.62₂×10_{_}¹²cm/dyne S₃₃=0.50₈×10^-12cm/dyne S₄₄=1.92₈×10^-12cm/dyn S₁₂=-27₇×10^-12cm²/dyn S₁₃=-0.16₃×10^-12cm²/dyn The elastic anisotropy for Young's (E) and rigidity (n) modulus is E_??_/E_??_=1.22, n_??_/n_??_=1.03 respectively.

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The absolute temperature is a measure of energy, as was clarified by Lord Kelvin. Hence, it was inferred that the interval rule existing in the anomalous temperatures of Cu, i.e., (0°K_??_230°C):(230°_??_550°)=3:2 and (0°K_??_277°C); (277°_??_1083° m. p.)=2:3, is no other than the Landé's interval rule of the fine structure of atomic spectra, saying that the interval ratio for the term of odd multiplicity, is equal to a ratio of a sequence of natural numbers. Accordingly, the anormalous temperatures of Cu, including 0°K, namely 0°K, 277°C, 1083° m. p. and 0°K, 230°C, 550° correspond to the components of E₁ and E₂, respectively, which were already determined from X-ray spectrum; the anmalous temperatures corresponding to E₃ and E₄, are expectable to exist in a range of low temperature.

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The stress restored in steels (0.6, 0.9% plain carbon and 0.3_??_0.9%, C, 3% Ni steels) variously heat-treated has been measured, the dimension of the specimen is 4mm×9mm×100mm. Some quenched specimens consisted of a single structure and some were heterogeneous. In the case of a single structure, the stress-depth curve was always simple and had no maximum or minimum point while in the case of heterogeneous structure the curve had a minimum point, generally. In all cases of the single structure, the stress was maximum at the surface and was always in tension. In the case of all martensitic structure, the maximum stress at the surface was not larger as the content of the carbon increased. In the case of the stepped quenching, the stress increases as the temperature of the second quenching elevates from Ar'' point and attains a maximum and then decreases. The stress at the surface of the quenched specimen whose structure is uniform were as follows. martensite>troostite>sorbite>pearlite
In the case of austempering above 480°, the residual stress was very small.

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When α iron is corburised, it readily transforms into γ iron as it absorbs carbon. By this phase change, the austenite grain formed at the surface of the specimen develops a columnar form towards the in side. When the alloy corsisting if α and γ at the temperature of the carburisation is rarburised no such columnar grain is obtained. These facts are similar to those of the case in which the austenite or a mixture of austenite and ferrite are decarburised, reselting in columnar or granular ferrite.

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A few considerations have been given on the effect of carbon and silicon upon graphitisation of white cast iron.

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If we dip Cu and its alloys in methanol, their surfaces become black brown in colour. The degree of corrosion differs according to the kind of metals ard the methanol used. The pure methanol does not act upon Cu and its alloys, the long stocked methanol produces corrosion. By the Electron-Diffraction method, we know that the corrosion product is Cu₂O. Conclusively, the corrosion mechanism of Cu and its alloys in methanol is thought to be as fallows. -
1. The methanol is oxydized in the air partiary, and produces some formaldehyde and formic acid. The produced formic acid dissolves Cu and its alloys.
2. Partiary Cu and its alloys produce the Cu-methylate.
3. The soluble Cu-formate is red-oxzdized by formaline and metalic Cu with the catalyser of the Cu-methylate, and then Cu₂O is produced.

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Researches were carried out on some corrosion poenomena with pu_??_e tin metal, and the work was advanced to the tin base binary alloys. Here reported are the prelimina_??_y results obtained by using Sn-Al, Sn-Bi, Sn-Cd, Sn-Cu, Sn-Pb, Sn-Sb, and Sn-Zn, the corrosives are HCl, H₂SO₄ and HNO₃ solutions.
The results obtained are shown in Tables 1 to 7 in the original paper.

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The effects of Cr, Al, C, Si and Mn on the properties of Fe-Cr-Al electric Leating wires were investigated. The effects of Al and Si on erectric resistance were most remarkable and oxidation resisting property was improved by Cr, Al and Si. The properties of cold working were improved by rapid cooling after soft annealing. This is explained from the relations between the solid solubility of (CrFe)₄C to α solid solution and temperature. Ta was most effective to prevent the grain growth of wire caused by heating at high temperature and secondly Zr, Ti and V were effective.

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