EXACTLY what drove two men to pretend to be archaeologists and hack off pieces of the Great Pyramid? Atlantis. It's a tale of cranks, conspiracies and an ancient cartouche. The Great Pyramid of Khufu (also known as Cheops) on the Giza Plateau is the largest pyramid in Egypt and the only surviving example of the Seven Wonders of the Ancient World. The cartouche? It's an ancient red-pigment scribble deep inside the Great Pyramid said to be the linchpin in identifying who it was actually built for. Is it an authentic ancient Egyptian depiction of his name, or a 19th century...