1996A&A...308..713F

Large-scale images in linear optical polarisation of three edge-on spiral galaxies (NGC 891, 5907, 7331) are presented. The dominant orientation of the polarisation pattern in all observed galaxies is perpendicular to the major axis and seems to be given by anisotropic scattering effects. However, we also found evidence for polarisation due to the Davis-Greenstein mechanism. In a region located towards the central part of NGC 891 within the dust lane, the derived orientation of the magnetic field is perpendicular to the major axis. In NGC 7331, the polarisation along the western dust lane indicates a toroidal field. No other indication for disk-parallel (toroidal) magnetic fields in the observed galaxies could be found.