The young man sees that the quickest way to get them started is to obey, so he manages to reach the saddle in front of the professor, who clasps his arms about him and holds on.

This done, they clatter on again.

It soon becomes evident that their pursuers gain upon them rapidly, despite their best efforts.  There can be but one end to the race, and this is in plain view.

John keeps his wits about him.  If caught upon the open by the rushing column of fierce desert warriors, a desperate engagement must ensue, which will doubtless end in their complete annihilation, for it can hardly be expected that Sir Lionel will be able to play his great game twice on the same night.

The Englishman has maintained a stolid silence all this while.  Perhaps he is out of humor at the change in the arrangements, and fears lest, after all his hard work, the young Chicagoan may carry off the palm.

Past experience has been of that order.

Hence he moves without much animation.  There seems to be a fatality about the sudden appearance of Doctor Chicago on the scene.

Meanwhile John Craig is not bothering his head about the small side-issues connected with the matter, which will work out their own final adjustment.  He is more concerned regarding their escape from the threatening doom that seems ready to ingulf them.

Something must be done, that is certain, beyond all peradventure, and John quickly grasps the situation.  There is no disease that does not have its remedy, and he finds a loop-hole of escape here.

As they gallop along they come to a structure built upon the road-side—­a singular affair it was once upon a time, being made of stone.  John recognizes features that tell him this deserted place was once a holy spot, the tomb of a marabout, or saint, built in a manner to suit the taste of the departed.

It has been long deserted, as too public, and the holy relics moved to some more secluded tomb within the walls of the cemetery on the high hill of Bouzareah.

This is their chance.

To continue the race means positive overhauling and doubtless death, while by accepting the chance that fortune has thrown in their way they may keep their enemies at bay until aid comes, for John has not forgotten the mission of Monsieur Constans.

He calls a halt, and briefly explains his plans.  All of them see that the horses they ride are not in the race when compared with the magnificent steeds of their pursuers, and recognizing the fact that what John suggests is probably the best thing to be done under the existing circumstances, they quickly dismount.

The horses are then started along the road in the hope that they will lure the pursuers on while the little party pass through the opening, and enter the quaint building, once the resting-place of a holy Mohammedan’s bones.

CHAPTER XX.