We have constructed the double magnetic lens β-ray spectrometer. Its geometry is shown in Fig. 1. We have tried the methods of Quade and Halliday to set the axis of the lens coil and the cylinder, the data of which was reported already. This paper includes the calculated values of the electron orbits and the resolving powers and the experimentally evaluated value of the energy .constant of the instrument by the analysis of the Co⁶⁰–γ.

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The penetrating bursts under the thick lead plate were studied by a fast ionization chamber at 2740 m altitude. The bursts are classified with respect to the number of secondary particles which penetrate 7 cm lead under the chamber. The bursts containing one or no penetrating secondary particle are interpreted mainly as the nuclear stars produced in the wall of the ionization chamber. Most of the cases in which the bursts contain two or more penetrating particles are explained as the electronic shower accompanied with the hard shower. For these events it is plausible to take into account the gamma decay of the neutral meson.

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By means of models of intermolecular potential U(r), the total energy of molecular crystals is calculated provided the additivity of intermolecular forces is valid. If the Lennard-Jones model, U(r)=U₀(s−6)⁻¹[6(r₀⁄r)^s−s(r₀⁄r)⁶], is used, the lattice of hexagonal closest packing has always a lower energy than that of cubic closet packing. If the model, U(r)=U₀(σ−6)⁻¹[6exp(σ−σr⁄r₀)−σ(r₀⁄r)⁶] is used, there is a critical value of σ, σ₀=8.675, above which the hexagonal is stable and below which the cubic is stable.
In general, in order that the cubic structure has a lower energy as in the case of rare gases, it is necessary (although not sufficient) that the hollow part of the intermolecular potential is wide enough, much wider than that of U(r)=U₀[r₀⁄r)¹²−2(r₀⁄r)⁶] for instance.
These results are in agreement with the conclusions which Kihara has obtained by investigating the third virial coefficients of the equation of state for rare gases.

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A very simple derivation of well-known Mollwo’s relation between ionic distance and F maximum absorption frequency is given. Then, following Inui and Uemura’s idea, the variation in the position and the breadth of F absorption band with temperature is correlated with the variation and the fluctuation in ionic distance by thermal motions. Finally, formula for the concentration of F centers in equilibrium with alkali vapor is given, taking into account the change in vibrational frequency of the positive ions adjacent to F vacancies. Numerical value for the parameter characterizing this change is computed by comparing with experiment the formulas for the temperature dependency of F band and for the concentration of F centers.

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The same interpretation of V₃ center as that of Seitz is given. The energy of formation of a V₃ center in the crystal from a molecule of a halogen gas is computed and compared with Pohl’s observation. The computed value in the case of KBr is 1.4 ev. as compared with the observed value 1.2 ev. Further, the mobility of V₃ centers at high temperature is discussed and a theoretical formula is derived for it. The computed value of the activation energy for the mobility in KBr is 1.2 ev., while the corresponding observed value is 0.7 ev.

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The dielectric constant of Rochelle Salt was measured at 3000 mc/s. using a new method in which the dielectric constant is obtained by measuring Q of a rectangular H₁₀₁ mode cavity, one E-plane of which is closed by Rochelle Salt surface.
The dielectric constant at this frequency is smaller than that at lower frequencies, though it shows two peaks at the Curie points.

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Internal friction of ferromagnetic substance cooled in longitudinal magnetic field is studied both theoretically and experimentally. Two theories are developed on the basis of two different ideas on the elementary magnetizing process. The first theory which assumes that the substance is magnetized by the displacement of 180°-domain boundary leads to the conclusion that internal friction at the demagnetized state must vanish by field-cooling. The second theory assuming that the substance is magnetized by the reversible and irrevarsible rotation of spontaneous magnetization concludes that internal friction at the demangnetized state must increase appreciably by field-cooling in contrast to the former case. On the other hand, experimental investigation of both field-cooled and commonly annealed substances is carried out for Ni₃Fe. Comparing the experimental and two different theoretical results, the latter theory is known to be more convenient to explain the measured data than the former theory. The magnetic domain structure of field-cooled substance is so concluded from this investigation that the spontaneous magnetization in the substance is fixed to the direction closer to the applied magnetic field than in usually treated substance, and that the magnetizing process is still rotation of spontaneous magnetization from the newly fixed direction.

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The magnetic after effect in 65-permalloy under various tensions was observed. In this case the reversal of magnetization occurs in several or a single Barkhausen jumps according to the amount of the applied tension. The value of dB⁄dH along the descending branch of the hysteresis curve has a very sharp maximum with comparatively narrow breadth. In the cases for small tension, magnetization in the course of after effect shows almost no change until the time t reaches a critical value t_c, and after t_c changes in the usual manner of the after effect. The value of t_c, decreases with decreasing final field. When the total reversal of magnetization occurs in a single Barkhausen jump, even a slight change in the magnetization can not be observed until t_c, and the whole reversal takes place in a very short time interval after t_c. These can be interpreted on the assumption that the after effect is closely related to the irreversible displacement of domain boundaries.

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Variation of inner energy for Ni₃Fe with time of the annealing at critical ordering temperature 490°C are observed first by measuring the excess specific heat of the specimen annealed with various duration, and secondly by measuring the rate of decrease of inner energy at 490°C using a new experimental method in which the necessary difference of temperature between the specimen and the surrounding wall for keeping the specimen at constant temperature 490°C is measured. Then, the variation of inner energy shows a tendency of two steps character which had been observed until now for many other physical quantities of this alloy. Next, this phenomenon has been analysed as a simple superposition of two kinds of formation processes, i.e., a formation of short range order, which starts abruptly from the beginning and ends at about 15 hours of annealing, and a formation of long range order, which begins with a sufficiently small rate, increases gradually to its maximum at 20∼30 hours and then decreases to zero at about 60 hours of annealing.

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From the more detailed analysis of the proton magnetic resonance absorption in hydrogen perchlorate monohydrate described in the preceding paper, the pyramidal structure of the oxonium ion is again confirmed.

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Forced oscillations of systems with nonlinear restoring forces are treated rigorously in certain special cases which are specified by the condition that the harmonic oscillation has a similar wave form to that of the external force. From this condition we are led to the introduction of the external force represented by the function cn for a hard system and by the function sn in the case of a soft system, and consequently the solution is given by either of these functions. Response curves obtained are similar to the corresponding response curves which have been given by approximate solutions. To examine the stability of the forced oscillation one must solve Hill’s equations, which can be carried out exactly in the present cases. Thus, the stable or unstable regions in the response diagrams are determined definitely and a few questions are clarified.

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In the isotropic turbulent field, energy spectrum was observed by an improved equipment. The measurements were made in a closed channel which was added to the exit cone of an open-type wind-tunnel. A voltage integrator was used to read the fluctuating output of low-frequency components. Low-cut filter attached to the input terminal increased the accuracy at high-frequency region.
Measured spetrum curves are nearly the same as previously reported. The decay of spectral components is severer at high wave-number throughout decay process. The energy transition is estimated from the measurements above mentioned. The wave-number of zero transition decreases as the turbulence decays. Finally, the gradient of spectrum curve is determined by differentiating the spectrum with respect to wind-speed. At medium wave-number region the power index is about -5/3. Three dimensional spectrum is also obtained by this method.

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Bethe’s dynamical theory of election diffraction has been extended by an approximate treatment first to the case of a wedge-shaped crystal, next to the case of a wedge-shaped crystal covered by opaque screens with an aperture and finally to the most general case of a polyhedral crystal of finite extension. If the incident wave, Φ_I=Ψ_Iexpj(K_I·r), impinges on the entrance surface, S_e, and the transmitted and diffracted (interfracted) wave leave the crystal from the exit surface, S_a, their wave functions are given as a superposition of plane waves;
the transimtted wave: Φ₀(r)=∑_i=1,2∫Ψ₀⁽ⁱ⁾(K₀)expj(K₀·r)dK₀
the diffracted wave: Φ_g(r)=∑_i=1,2∫Ψ_g⁽ⁱ⁾(K_g)expj(K_g·r)dK_g
Here, the amplitude functions, Ψ₀⁽ⁱ⁾(K₀) and Ψ_g⁽ⁱ⁾(K_g), are as follows;
Ψ₀⁽ⁱ⁾(K₀)=Ψ_I∫\fracc⁽¹⁾c⁽²⁾c⁽¹⁾−c⁽²⁾·\frac(−1)ⁱc⁽ⁱ⁾·L(K_I−k₀⁽ⁱ⁾;Se)L(k₀⁽ⁱ⁾−K₀;Sa)dk₀⁽ⁱ⁾
Ψ_g⁽ⁱ⁾(K_g)=Ψ_I∫\fracc⁽¹⁾c⁽²⁾c⁽¹⁾−c⁽²⁾(−1)ⁱL(K_I−k₀⁽ⁱ⁾;Se)L(k_g⁽ⁱ⁾−K_g;Sa)dk_g⁽ⁱ⁾
where c⁽ⁱ⁾ is the amplitude ratio of the primary and secondary (interfracted) waves in crystal which are related to the i-branch of the dispersion surface, and k₀⁽ⁱ⁾ and k_g⁽ⁱ⁾=k₀⁽ⁱ⁾+2πg are their wave vectors. The function L means the diffraction function due to an aperture S and expressed as
L(K−k;S)=∫_sexpj(K−k·r_s)drs.
The most general expressions of the transmitted and diffracted waves for a finite polyhedral crystal are given as the sum of the waves mentioned above for every pair of the entrance and exit surface.

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The general formula derived in the previous paper has been simplified by introducing an assumption that the wave-length of electrons compared with crystal size is very short. The simplified formula is more practical and directly applicable to the interpretation of the simple- and double-refraction as well as the Fraunhofer diffraction effects of Laue spot. A comparison of the dynamical and corresponding Kinematical formulae shows that the concept of “Intensitätsbereich” as advocated by von Laue in his kinematical theory may be used in dynamical theory. Finally some numerical examples and comparison with theory and experiment are given.

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The absorption properties of the flashed barium getter beyond 0°C were studied. At low temperatures, carbon mono-oxide was apparently absorbed by the getter, while its resistance remained almost unvaried. At higher temperature than about 150°C, however, the resistance changed remarkably as the getter absorbed the gas. The ionization of the introduced gas made the absorption of the getter slightly vigorous. In the c.f. method the pressure decreased at first to a minimum value and then it began to increase, suggesting that another kind of gas was formed by the catalytic action on the getter surface. The phenomena were studied in details. The alternative introduction of carbon mono-oxide and oxygen gave a clue to the absorption state of carbon mono-oxide.

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The theory presented in Part II was also applicable to the gettering process at room temperature. The activation energies for the activated adsorption of carbon mono-oxide and for the desorption of carbon dioxide, having been formed by the catalytic action, were estimated to be 7.5 and 8.8 Kcal/g.mol respectively. At higher temperatures than 150°C, some kind of compound was formed and the conductivity of the getter mirror changed remarkably. In addition, the probable state of aetivated adsorption of carbon mono-oxide on the getter surface will be postulated.

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La surface du foyer d’éclatement du verre a été observée avec le microscope électronique. Nous avons observé surtout les petits corps ronds qui se trouvent dans l’endroit lisse du foyer d’éclatement. Nous concluons que ces petits corps sont peut-être des cassures en forme de lentilles qui se produisent parallèlement à la surface de la cassure principale au cours de la rupture soudaine du verre.

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