chunk: Guided by the Psammead the children purchase an ancient amulet in the shape of an Egyptian Tyet (a small amulet of very similar shape to the picture can be seen in the British Museum today), which should be able to grant them their hearts' desire: the safe return of their parents and baby brother. But this Amulet is only the surviving half of an original whole. By itself, it cannot grant their hearts' desire. Yet it can serve as a portal, enabling time travel to find the other half.