unanswered 9:11 questions, page-110

marzipan9, Yeas the slag from welding is from the flux and steel but it is similar to the oxide from a cutting torch or lance maybe not as strong though. It just looks too intact too have had the whole building come down around it without knocking at least some of it off. Just my observation. Have also seen other pictures somewhere on the webb of workmen cutting on diagonal when removing upright beams at the trade centre. not sure if they cut on an angle to help with keeping the cut from fouling with the slag, oxide or it is to drop the beam a certain way. I think it may be the former as in the other pictures I had seen I think they had a crane attached to the beam. Cheers spanner