Next morning, sure enough, the Sheikh returned with a donkey, led by a slave, and bearing on its back a fine fat sheep. Suitable greetings were exchanged and, a couple of hours after sunrise, the caravan was off. Tamia was left behind, the last point of civilization was broken with, and during the rest of the stay in the desert only a constantly moving line of camels could keep the expedition in water and supplies.

“It’s like the commissariat of an army,” said Perry, when he realized this; “if our line of communication was cut, we’d be starved out.”

“Yes, yes,” Antoine agreed, “it is a serious matter to be out of reach of water, but we can depend on Mr. Wyr; he knows all that is necessary to do in Egypt.”

The march out from Tamia was over very different country than the road over the small stretch of the Libyan desert passed on the westward march from Lisht the day before. It was low and shingly, with little scattered tufts of vegetation; and seemed to be part of a huge saucer-like depression.

“Is this the Fayum?” asked Perry.

“This is the very site of Lake Moeris,” the professor answered, “an artificial lake made by Amenemhat III. It used to be quite a famous resort in Greco-Roman times, Perry, and almost anywhere around you might find Roman coins if the Roman boys used to play pitch-and-toss, as Juvenal and some of their writers say the urchins did.”

“Right here?”

“Right on this very spot.”

“But where has the lake gone?”

“Dried up,” was the answer. “A great deal more land is irrigated in the Fayum than used to be the case, so that the water from the old canal of Joseph, the Bahr Yusuf, has more work and less overflow. That canal, by the way, Perry, was made so long ago that even tradition has forgotten about it, and it was supposed to be a natural river until recently.”