So the _Korosko_ had been taken, and the chances of rescue upon which they had reckoned--all those elaborate calculations of hours and distances--were as unsubstantial as the mirage which shimmered upon the horizon.

There would be no alarm at Halfa until it was found that the steamer did not return in the evening.

Even now, when the Nile was only a thin green band upon the farthest horizon, the pursuit had probably not begun.

In a hundred miles, or even less, they would be in the Dervish country.

How small, then, was the chance that the Egyptian forces could overtake them.