I took the shoe by the toe and hefted it: the flexible sole gave it a good action, like a well-made sap. There were still a couple of 'if's' in the equation, but a healthy crack on the screw ought to drive it against the packed match-heads hard enough to detonate them, and the expanding gasses from the explosion ought to exert enough pressure against the glass panels to break them. I'd know in a second. I flattened myself against the wall, brought the shoe up, and laid it on the screw-head with everything I had.... There was a deafening boom, a blast of hot air, and a chemical stink, then a gust of cool night wind--and I was on the sill, my back to the street six hundred feet below, my fingers groping for a hold on the ledge above the window. I found a grip, pulled up, reached higher, got my feet on the muntin strip, paused to rest for three seconds, reached again.... I pulled my feet above the window level and heard shouts in the room below: "--fool killed himself!" "Get a light in here!" I clung, breathing deep, and murmured thanks to the architect who had stressed a strong horizontal element in his façade and arranged the strip windows in bays set twelve inches from the face of the structure. Now, if the boys below would keep their eyes on the street long enough for me to get on the roof-- I looked up, to get an idea how far I'd have to go--and gripped the ledge convulsively as the whole building leaned out, tilting me back.... Cold sweat ran into my eyes. I squeezed the stone until my knuckles creaked, and held on. I laid my cheek against the rough plaster, listening to my heart thump. Adrenalin and high hopes had gotten me this far ... and now it had all drained out and left me, a frail ground-loving animal, flattened against the cruel face of a tower, like a fly on a ceiling, with nothing between me and the unyielding concrete below but the feeble grip of fingers and toes. I started to yell for help, and the words stuck in my dry throat. I breathed in shallow gasps, feeling my muscles tightening, until I hung, rigid as a board, afraid even to roll my eyeballs for fear of dislodging myself. I closed my eyes, felt my hands going numb, and tried again to yell: only a thin croak emerged. A minute earlier I had had only one worry: that they'd look up and see me. Now my worst fear was that they wouldn't. This was the end. I'd been close before, but not like this. My fingers could take the strain for maybe another minute, maybe even two; then I'd let go, and the wind would whip at me for a few timeless seconds, before I hit....