While the International Stock Exchange in London displayed its contempt for the IRA and all its bombs by carrying on trading after the blast that ripped a great hole in the side of the Stock Exchange Tower on Friday, someone put a bomb under Storage Technology Corp shares on Wall Street and trading had to be suspended to prevent a disorderly market after a wave of selling pressure which drove the shares down to an indicated $25 from $28.625 at the last firm trade: the company was bemused by the development and said it knew of no aspect of its business that could account for it, noting that its second quarter figures were solid (see page five) and in line with expectations; a possible cause could be that someone had got wind of a planned IBM product that would compete with the tape library.