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We investigate the influence of the solar atmospheric temperature stratification on the amplitude of waves at different heights and its dependence on frequency and wave number. Special interest is taken in the influence of atmospheric layers on the appearence of the recently observed p-mode crossing features and their location in the Fourier domain. We consider four stratification models. One of them is the standard model with convection-zone, VAL-atmosphere and corona. The others are modifications of this model in order to discuss the influence of specific layers of the atmosphere. The changes in the temperature structure significantly influence the velocity amplitude at certain frequency-wave number combinations at certain heights.

Short period oscillations (with periods less than 150 s) are shown to be non-uniformly distributed on the solar surface, and in time. Rather, they appear concentrated in short bursts which preferentially occur in regions with strong instantaneous downflow motion throughout the observed extent of the solar atmosphere.

Photoelectric polarisation measurements in a stable sunspot (type H) with a particularly dark umbra carried out with the Capri magnetograph have been evaluated in terms of Unno's (1956) theory to give the value and direction of the magnetic field vector. A linear increase of the inclination angle with distance from the spot centre up tor ≈ 1.2Rs results, as originally found by Hale and Nicholson (1938) with a different procedure. The field strength decreases from the maximum value (about 3300Γ) to about 15% at the penumbral border, still continuously decreasing outside the spot. The projected field direction deviates considerably from the radial symmetry in several parts of the spot region, but it is in good agreement with that of the overlaying chromospheric structures.