Dr. Cairn dropped into an armchair, nodding towards Sime.
"Tell him all that we have heard," he said. "We stand together in this affair."
"Well," continued Sime, in his deliberate fashion, "when we struck our camp beside the Pyramid of Méydûm, Ali Mohammed remained behind with a gang of workmen to finish off some comparatively unimportant work. He is an unemotional person. Fear is alien to his composition; it has no meaning for him. But last night something occurred at the camp—or what remained of the camp—which seems to have shaken even Ali Mohammed's iron nerve."
Robert Cairn nodded, watching the speaker intently.
"The entrance to the Méydûm Pyramid—," continued Sime.
"One of the entrances," interrupted Dr. Cairn, smiling slightly.
"There is only one entrance," said Sime dogmatically.
Dr. Cairn waved his hand.
"Go ahead," he said. "We can discuss these archæological details later."
Sime stared dully, but, without further comment, resumed: