A new article in the Open Chemical Physics Journal details chemical evidence from the 9/11 dust of thermite cutting charges.
One of the strongest pieces of evidence that the Government's account of 9/11 is flawed has always been the way in which the Twin Towers fell. They fell straight down, not to the side. Therre was the sound of explosions in the basement reported by firefighters. And most crucially: the speed of the fall was so rapid that there could not have been any resistance. In other words, the "legs" of the building must have been pulled out from underneath long before the weight of the falling top part came crashing down upon them. In fact, the buildings fell in "free-fall" time, the same time it would have taken a baseball dropped from the top of the buildings to hit the ground.
Physicists and engineers point out thata building cannot fall straight down 'by accident'. The way the buildings fell was characteristic of controlled demolition, in which carefully-timed cutter charges sever the supporting members at just the right times to make the building fall inward and not topple to the side. The science of controlled demolition involves some very critical timing, and even small mistakes can lead to the building falling over sideways instead of straight down.
Direct evidence in the past for controlled demolition has included photos of neatly-severed beams in the demolition clean-up. The beams did not appear to be twisted or melted, but rather cut in neat, diagonal straight lines.
Also compelling is the fact that a third WTC tower, known as Building 7, came down in the same fashion, falling straight down in free-fall time, landing in its own footprint. Building 7 came down late in the afternoon, hours after the Twin Towers, and Building 7 was never hit by an airplane. Building 7 was nowhere mentioned in the official report of the 9/11 Commission, and there are (besides controlled demolition) there are no 'official' theories how it fell so suddenly and symmetrically.
In this context, the new journal article provides corroboratory evidence that dust collected locally the afternoon of 9/11 and the following day contains microscopic traces of thermite. Thermite is a very hot-burning mixture of finely-powdered aluminum and finally powdered iron oxide. As hot as an oxy-acetylene torch, it is used to melt iron beams and cut through them. Fires burning paper, building materials, or even jet fuel do not burn nearly hot enough to melt steel. The authors note that the particles were milled to an extremely fine dust and intermingled so that they burn much hotter and more rapidly even than conventional thermite.