sound, the kind of sound you hear when a plane is, you know, going fast past you. followed by an enormous crash. and an immediate explosion. i don't think we could feel shockwaves, but we sort of felt like we did. we were in a position where we could see the trade center almost immediately between the other buildings. and an enormous fireball that must have been 300 feet across was visible immediately. a secondary explosion, i think, and then plumes of smoke. must have been a three-block cloud of white smoke. now, from where i was on the street a moment ago, you can, in fact, see smoke leaving the building on three sides. it seems to be coming out on at least four or five floors. the air is filled with hundreds of thousands of pieces of paper that are just sort of floating like confetti. the area is swarmed with emergency vehicles. and sirens.