Cell parameters of four natural orthopyroxenes were measured by X-ray powder method at high temperature.
The linear thermal expansion coefficients were calculated from their temperature derivatives. The present values are different significantly from those of a previous work.
Possibly, there is a positive correlation between linear thermal expansion coefficients and linear compressibilities for isotropic solids with the same crystal structure. This correlation holds also for each crystallographic axis of the present orthopyroxenes and the other anisotropic materials with a few exceptions.

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Laboratory experiment has been made on the fracture of ice under uniaxial compression. The shape and the dimension of micro-cracks are directly observed and the elastic waves accompanied by the formation of cracks are correctly recorded by using a oscilloscope. The wave forms of the elastic waves are analyzed by the method used in seismology. The rise time of the displacement source time function is obtained to be a few micro second for the crack with the dimension 1×2cm.
Properties of crack generation during the plastic flow are discussed.

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The effect of grain boundary to the phonon thermal conduction is estimated. As for a model, for the grain boundary the dislocation wall model by Read and Shockley is adopted and a phonon is taken as an elastic wave.
The effective thermal conductivity of boundary layer k, to be related to the scattering of the wave, is introduced and compared with that of the normal crystal k_n, and that of the glass k_g. The value k is obtained to be nearly the same as that of k_g. This shows that for the thermal conduction, the grain boundary may be taken as a thin glass. If a mean grain size is greater than several hundreds of Å, the grain boundaries do not affect the bulk thermal conduction, since k≅k_g.

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The resistivity variometer has been at work at Aburatsubo, Kanagawa Pref., about 60km south of Tokyo, since May 14, 1968. During the 6-year period up to June 30, 1974, of the resistivity observation, more than 25 records of coseismic resistivity change have been obtained in association with remarkable earthquakes.
The major results have already been summarized by the writer. This paper presents a conclusion about a detectability of the resistivity variometer system at Aburatsubo. Magnitude (M) of each earthquake which occurred in these 6 years is plotted against logarithmic epicentral distance (Δ). Almost all earthquakes, for which coseismic resistivity change are observed, fall on the upper boundary of the line, M=2.5log10Δ, where Δ is measured in unit of km.
Following the strain and epicentral distance relation by WIDEMAN and MAJOR (1967), the resistivity variometer at Aburatsubo can detect a strain change of the order of 10^-9 or thereabout.
This at the same time indicates that small earth's strain of the order 10^-8 can be detected with magnification factor of 10⁴ or so by the resistivity variometer.

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The earthquake, which occurred near Teshikaga, on Nov. 4, 1967, was accompanied by slight property damage in Teshikaga and its vicinity.
It is found that V_P/V_S observed at Abashiri Meteorological Observatory for earthquakes that occurred in Teshikaga-Akan area, showed unusual low values prior to the above mentioned earthquake, and returned to the normal value after this earthquake. This result is briefly discussed in relation to the dilatancy theory of earthquakes developed by Scholz and others.

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All the silicatube extensometers at Mikawa Crustal Movement Observatory are specially designed to detect strain steps associated with earthquakes with the use of two or three detectors for each silicatube. Various tests indicate that these instruments are sufficiently stable even for shocks as large as felt earthquakes. Since 1972, seven earthquakes have shown apparent strain steps, the minimum of which is as small as 5×10^-10. These strain steps are concordant with DAMBARA'S formula (1966), who investigated the relation of magnitude to the radius of region where crustal deformation can be observed. If we assume that the strain step decreses with distance as R^-2.5, where R is the epicentral distance, the strain step at the distance defined by DAMBARA is found to be 5×10^-6.

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Seismic intensity maps reported by the Japan Meteorological Agency are used for the study of seismic wave attenuation. Intensity maps between 1961 and 1964 were more detailed than now, because the observation of intensity by unofficial stations as well as those by the Japan Meteorological Agency were avairable. Some intensity maps show such a remarkable distribution that felt area is bounded by the volcanic front. It seems that waves cannot go across the volcanic front. Judging from the distribution of volcanoes, it would be better to think that this low-Q zone may not be homogeneous beneath the volcanic front. The Q value must be lower beneath the active volcanoes than the less active volcanoes.
The abnormal intensity distribution by shallow earthquakes may not be due to the high-Q lithosphere but to the heterogeneity in the crust. From the seismograms recorded at Inuyama seismolgical observatory, it is concluded that the low-Q zone exists beneath the volcanic front near the Izu peninsula where volcanic activity is high. A Q-model under the southern part of the Chubu district, central Japan, is proposed to account for both characteristics of seismograms and abnormal intensity distribution. The model consists of two low-Q zones. A shallower one may be related to the volcanic activity, and the other, to the down going lithosphere. There remains a high-Q zone between two low-Q zones.

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