Our previous determination of the limb effect for three medium strength iron lines has indicated that the centre to limb increase in wave-length is accompanied by an asymmetry in the line profile. In order to verify this result, which is of great importance for the theory of limb effect, true profiles of the three lines are now obtained at various disk positions and in particular at the extreme limb. These observations reveal a slight violet asymmetry at the centre of the disk and a strong, fluctuating red asymmetry at the extreme limb. The latter appears to be a chromospheric effect and is of sufficient magnitude to account for the super-gravity shift found in the earlier red-shift investigation. From this it is concluded that future investigations of red-shift and limb effect must include line profile observations.