BET SHEMESH, ISRAEL—Investigators working with the Israel Antiquities Authority have claimed David used an illegal "ghost" sling in his famous battle with Goliath. Experts allege the ghost sling would have been untraceable, which would account for why Goliath was caught off guard so easily. "Goliath, a man who stood about 7'10" by modern reckoning, would not have been defeated so easily if David had a legal sling registered with the proper authorities," said Dr. Phil Gath, a professor at the Hebrew University of Jerusalem. "David probably used a 3D printer or something, maybe he just stole some leather and grabbed...