Some years ago I was taken on a conducted tour of a newly privatised former Royal Ordnance factory which was making anti-tank rounds from both tungsten and depleted uranium – two metals of round about the same density. I don't really understand the physics of it, but apparently these heavyweight bullets don't penetrate the armour as a conventional rifle bullet might, but generate so much heat on impact that the armour-plate steel is melted locally, and a shower of liquid steel is released on the inside – enough to wreck internal machinery, set off explosive shells, and, of course, kill the crew. Not a very pleasant subject, and I was glad to get out. Small bonus was that they gave me a set of tungsten darts. I'm not really a player, but I understand tungsten-bodied darts are so slim that three will fit together in the treble 20 bed. Remember the TV commentator's cry of ONE HUNDRED AND EIGHTEEEE!