We start with the fact that large quantities of molten metal were observed in basement areas under rubble piles of all three buildings: the Twin Towers and WTC7. A video clip provides eye-witness evidence regarding this metal at ground zero:
http://plaguepuppy.net/public_html/video archive/red_hot_ground_zero_low_quality.wmv . The photograph below by Frank Silecchia shows a chunk of the hot metal being removed from the North Tower rubble on September 27, 2001. Notice the color of the lower portion of the extracted metal -- this tells us much about the temperature of the metal and provides important clues regarding its composition, as we shall see.
Silecchia photo
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1. Molten Metal: Flowing and in Pools
There are several published observations of molten metal in the basements of all three buildings, WTC 1, 2 (“Twin Towers”) and 7. For example, Dr. Keith Eaton toured Ground Zero and stated in The Structural Engineer,
‘They showed us many fascinating slides’ [Eaton] continued, ‘ranging from molten metal which was still red hot weeks after the event, to 4-inch thick steel plates sheared and bent in the disaster’. (Structural Engineer, September 3, 2002, p. 6; emphasis added.)
The existence of molten metal at Ground Zero was reported by several observers (see first photograph above), including Greg Fuchek:
For six months after Sept. 11, the ground temperature varied between 600 degrees Fahrenheit and 1,500 degrees, sometimes higher. “In the first few weeks, sometimes when a worker would pull a steel beam from the wreckage, the end of the beam would be dripping molten steel,” Fuchek said. (Walsh, 2002)
Sarah Atlas was part of New Jersey's Task Force One Urban Search and Rescue and was one of the first on the scene at Ground Zero with her canine partner Anna. She reported in Penn Arts and Sciences, summer 2002,
‘Nobody's going to be alive.' Fires burned and molten steel flowed in the pile of ruins still settling beneath her feet. (Penn, 2002; emphasis added.)
Notice that the molten metal (probably not steel alone; see discussion below) was flowing down in the rubble pile early on; so it is not the case that the molten metal pools formed due to subterranean fires after the collapses.
A video clip provides further eyewitness evidence regarding this extremely hot metal at ground zero:
http://plaguepuppy.net/public_html/video archive/red_hot_ground_zero_low_quality.wmv. The observer notes that the observed surface of this metal is still reddish-orange some six weeks after 9-11. This implies a large quantity of a metal with fairly low heat conductivity and a relatively large heat capacity (e.g., iron is more likely than aluminum) even in an underground location. Like magma in a volcanic cone, such metal might remain hot and molten for a long time -- once the metal is sufficiently hot to melt in large quantities and then kept in a fairly-well insulated underground location.
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Dramatic footage reveals yellow-to-white hot molten metal dripping from the South WTC Tower just minutes before its collapse:
http://video.google.com/videoplay?docid=-2991254740145858863&q=cameraplanet+9/11. Photographs capture the same significant event, clearly showing liquid metal dropping from the South Tower, still hot as it nears the ground below:
photo - tower dripping molten metal
another photo
Who can deny that liquid, molten metal existed at the WTC disaster? The yellow color implies a molten-metal temperature of approximately 1000 oC, evidently above that which the dark-smoke hydrocarbon fires in the Towers could produce.
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Are there any examples of buildings toppled by fires or any reason other than deliberate demolition that show large pools of molten metal in the rubble? I have posed this question to numerous engineers and scientists, but so far no examples have emerged. Strange then that three buildings in Manhattan, supposedly brought down finally by fires, all show these large pools of molten metal in their basements post-collapse on 9-11-2001. It would be interesting if underground fires could somehow produce molten steel, for example, but then there should be historical examples of this effect since there have been many large fires in numerous buildings. It is not enough to argue hypothetically that fires could possibly cause all three pools of molten metal.