He knew he was almost there when he stumbled over a big hunk of ice-rimed 
stone. Picking it up, Peter saw that it was a jagged piece of black rock larger than his fist. A fragment of the former IBM Tower. Just ahead was a
four-square block area of ruined buildings where the IBM subtowers had fallen, 
crushing other buildings and setting off gas-line explosions that tore up the 
downtown area.