A GIANT illuminated poster with a pointing arrow at the new hi-tech bus boutique (it's far too fancy to be called a mere bus stop) between the Mandarin and the Hong Kong Club promises ''a haven of tranquillity only 139 steps this way''. We have no idea what that sign means. But what we know is that by taking a carefully measured 139 steps with only a slight deviation to the left the curious tranquillity-seeker would arrive right inside the Hong Kong Club's Bowling Alley Bar - a haven for retired colonels, grey taipans and a few senior administrators of justice taking refuge from the bench. An oasis of tranquillity, indeed. Alas, not anymore. For, horror of horrors, this last bastion of male supremacy has been breached. New rules have just come into effect allowing ''ladies'' to visit the bar after 6 pm. Ye Gods, is nothing sacred?