Distribution of the integrated line-of-sight RM in the four quadrants on the sky determined by the galactic edge-on disk and the positive rotation axis. We are looking along the negative y-axis relative to Fig. 1. The parameters of the magnetic field and of the flow field including rotation are as in the upper row of Fig. 1. Upper right and lower left images contain only negative RM values, while those at upper left and lower right are positive. The sign changes across the disk and across the axis to give the characteristic X configuration in the RM. The positive behavior is at upper left and lower right, while the negative behavior is at upper right and lower left.