“But these storms change about so, Excellency,” said the Sheikh. “This may suddenly turn back or rush off right away from us. It will, I think, go onward towards the great river away to our left, and sweep across it. No!” he thundered out. “Be ready; it comes,” for suddenly a hot blast of air smote the party, fluttering their robes, and the whirling pillars, so distinct and clear a few minutes before, grew misty as if seen through a dense haze; for by one of its sudden changes the storm had swept round almost at right-angles, and the next minute the sky was obscured, the camels were groaning as they buried their heads in the loose sand, and the storm of hot, suffocating dust, borne on a mighty wind, was upon them, shrieking, tearing at everything loose, and buffeting its victims, who could hardly breathe, the dust choking every tiny crevice in the cotton cloth held over the face.
The roar and rush were horrible, the confusion of intellect strange and peculiar, and Frank, as he cowered down behind his camel with his forehead pressed against the saddle to keep his veil in its place, felt as if he were breathing the scorching air out of some open furnace door, while the choking, irritating sensation in the air-passages seemed as if it must soon terminate in death.
Doubtless that would have been their fate if the storm had lasted; but as quickly as it had come upon them it passed over, and in a few minutes the air about them was clear again, the sky blue, and the sun beating down, while the dust-cloud pillars were careering along, distinctly seen a quarter of a mile away.
“Yes,” said the Sheikh calmly, “they are terrible, these hot whirlwinds. Their Excellencies would be glad to bathe and clear their faces and hair from the thick dust, but there is no water save for drinking. We have never had a worse one than this, Excellency, in our travels.”
“Never,” said the professor, who knelt in the sand trying to clear his eyes from the impalpable brownish dust, “and I don’t want to meet another. This is one of the experiences of a desert journey, Frank. Why, lad, you are turned from black to brown.”
“And you the same, but from white,” replied Frank, smiling.
“I suppose so. It’s bad for the Hakim’s white robes, too. I say, Ibrahim, when shall we strike the river?”
“Not for many days, Excellency; but we shall halt at fountains among the rocks.”
Five days’ monotonous journeying across the sandy plains, and then five nights of travelling, with the days devoted to rest, had passed before the river was approached at a bend which brought it near the line of travel which the Sheikh had traced out for himself by the stars. The way had been marked by the bones of camels, and in two places other bones scattered here and there told their horrible tale of suffering or attack, one skull displaying a frightful fracture that was unmistakable; fountain after fountain had been reached, and refreshing halts had been made where the waters gushed from some patch of rocks, to fertilise a small extent around, supporting a few palms and prickly, stunted bushes of acacia-like growth, before they started away again into the sand; and in cases where the next water-hole was too far, one, two, or three camels bore away water-skins well filled, to carry the party over the next halting-place.
The necessity of keeping up the supply forced their guide to adopt a zigzag mode of progression, and to make his little caravan traverse nearly double the distance that would have been necessary could they have taken a bee-line towards the south. But experience had taught all travellers who journey by the desert, instead of by the great waterway with its vast cataracts, where the pressure of the earth forced the water springs to the surface, and naturally these were the goals for which all tired travellers made.