10. This viewgraph shows the bulk flow in the direction of the massive Centaurus overdensity which is about 2000 km/s deep at a distance of 3500 km/s. There is no sign of a step in the flow pattern at this distance, the signature of infall; rather it occurs at a distance of 6000 km/s where the optical overdensity stops. Is there a massive dark attractor at this distance? Because the Centaurus overdensity infall is not detected, it signifies that the bulk flow on scales of 6000 km/s is very cold with a Mach number in excess of 4 (see Ostriker and Suto, ApJ, 348, 378, 1990). Therefore the density parameter must be small.
11. The Fornax Void is 2000 km/s deep. It should exert a strong push on the surrounding galaxies and should be a region of intense outflow. However there is no sign of this in our results.
12. Vpec. is plotted against predicted distance for the Centaurus overdensity, the errors in both co-ordinates are now correlated. The distance errors scatter points out of the overdensity and artificially produce the appearance of coherent infall toward the Centaurus system centred at a distance of 3500 km/s. This diagram would be incorrectly interpreted as a bulk flow of 370 km/s and an infall into the Centaurus overdensity of 370 km/s. This would yield a Mach number of 1 which is currently he value obtained by the POTENT analysis (Dekel, Ann. Review of Astronomy & Astrophysics, 32, 371, 1994),
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