The sounds defied description. In all recorded history, only one other 110-story building had ever collapsed, and that was twenty-nine minutes earlier. Everyone who heard it from the inside took the experience to the grave. Maybe the sound and fury rivaled an Everest avalanche, or a volcanic eruption, or a rocket launch. Or maybe not. Nothing matched being inside five hundred million fiery, falling pounds15 of twisting steel, crumbling concrete, disintegrating office furnishings, shattering glass, and ending lives.