Yet another fascinating report in Science News from the Archaeological Institute of America's annual meeting (previous post here), this time on the Sassanid/Roman battle in front of Dura-Europus in the mid-third century:
Although debris indeed blocked the entrance to the Roman tunnel, James doubted that explanation. First, he analyzed the positions of Roman soldiers’ bodies in the tunnel and determined that they had been deliberately stacked into a pile, either when they were mortally wounded or after they had died. The Sasanians apparently wanted to create a human wall between themselves and approaching Romans.
To obstruct advancing Romans, the Sasanians blocked the tunnel entrance with stones before stacking up the Roman victims. The Sasanians then threw a cloak and some straw on the Romans and set them on fire using a mix of pitch and sulfur. Signs of severe burning appear on the pile of skeletons and military equipment. Remains of pitch and sulfur crystals were found near the bodies, which had not been observed in earlier research, James reports.
Toxic fumes from the fire would have driven off any further Roman soldiers hoping to enter the tunnel, James said. One skeleton in the tunnel, lying by itself on the Sasanian side of the pile of bodies, is that of a helmeted Sasanian soldier carrying a sword. He apparently had set the fire and failed to flee before succumbing to the fumes, James suggests.
Full story here.