(1) A new type of oil vacuum gauge equipped with a specially designed compressing chamber is devised. (2) Mercury trap can be avoided in this gauge. (3) Due to the small density of oil, lower pressure can be measured. (4) The cylindrical oil reservoir with a piston is a convenient arrangement for changing the height of the oil surface: our reservoir has no need of using an exhausting system as in the case of a mercury reservoir used in some types of McLeo:l gauge, and no fear of driving the liquid into the vacuum tube by the mistreatment of stop-cocks. (5) Owing to the large viscosity of oil, however, it is impossible to use the gauge in the case when the pressure of gas is rapidly changing

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The experimental data concerning to β-ray radioactivity were analysed. In part I, mass differences of pairs of isobars, the Sargent relation and possible selection rule for β-transition are discussed for light elements. Mass differences are analysed in connection with the formula given by Wigner and by Barkas. From the Sargent diagram, essential agreement with Fermi theory was deduced. Only transitions between the pairs of isobars belonging to the same multiplet discussed by Wigner are allowed in strict meaning, while transitions between isobars which, satisfying the selection rule for spin and parity, do not belong to the same multiplet form a group, decay period of which is about 40 times larger than that of the former. More one group of transitions which are about 10^-4 times less probable as compared to the strictly allowed transitions might be those between isobars which do not satisfy the selection rule for spin and parity. Spin 0 to spin 0 transition is completely forbidden. In part II, the Sargent diagram for all radioactive elements is discussed and also Fermi theory seems, to be well applied to the interpretation of it. Allowed transition for natural radioactive elements belongs to the second group in part I and the forbidden transition to the third. From this it can be concluded that the heavy parties matrix elements for heavy -radioactive body will be of the same order as those for light elements provided that the change in nuclear structure is similar in both cases

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The method of investigating the resonance neutron groups of any nucleus which is not made radioactive by neutron capture by utílí zing the gamma-rays emitted in the capture process itself was extended to Cl, Co, Ag and Ba. The gamma-ray intensity was measured as a function of thickness of paraffin layer interposed between a D+D neutron source and a detector. As the intensity of the gamma-rays emitted front these nuclei was very small except the case of Ag, no such distinct results were obtained as in the case of Cd or of Hg reported in the previous paper. But, from analysis of the gamma-ray intensity curves, it can be shown that Cl has not any distinct resonance groups, Co has a group of about 10¹_??_10² e V. in energy, and Ba has a group of very high energy (perhaps of the order of 10³ e. V.). The result for Ag is in qualitative agreement with that obtained by the ordinary method of β-ray activity. In addition, the relative number of gamma-ray quanta emitted per capture of a thermal neutron was obtained to be 0.64, 0.74, 1.00 and 0.82 for Cl, Ag, Cd and Hg respectively. And these results were compared with those of the other investigators

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The author discusses the absolute meaning of the symmetric correlation coefficient between vector sets introduced in his previous paper in connection with the generalised Fourier coefficient

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