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Hall's theory of structural relaxation is applied to explain the excess ultrasonic absorption in methyl alcohol in the pressure range 1-2000 kg/cm . Two states, one characterized by a higher volume (icelike structure) and the other by a lo~er volume (close-packed structure), are assumed to be available to each molecule of methanol, just as in water. It is found that Hall s theory for this case must be modified in order to be in agreement with the experimental results. The modification consists in assuming that the variation of the volume difference &V and the free-energy difference &F is nonlinear with pressure, in contrast with water. This leads to excellent agreement with theory, and also to the conclusion that t';ie variation of AF with pressure is similar to that of ultrasonic velocity in methanol. Assumed values of the relaxational compressibility P"and the structural relaxation time v(at P =1000 kg/cm ) are also justified because the other parameters calculated are as expected.

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The electron-electron interactions in lithium metal have been examined keeping in view the recent developments. The contribution of the electron-electron Umklapp scattering processes in the electrical resistivity of lithium at low temperatures has been evaluated using a simplified spherical Fermi surface model with isotropic transition probability. Our values of the electrical resistivity so obtained compare fairly well with the experimental results for lithium.

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