“That boy has a good head for music,” was Canby’s quiet tip to Macauley.

Billy and Henri certainly earned their salt by the expert manner in which they set in order the flying fleet of the Turks, and the Moslem aviators that went out on scouting trips every day had no complaint of ill behavior on the part of the aeroplanes used by them.

It might be mentioned that two war-planes of British make, occupying space near to the open front of the bazaar building, were not neglected by the busy aeroplane experts. The tanks of these machines were kept filled to the brim, and every running part oiled to a nicety.

The prisoners were biding their time, and awaiting the golden moment when the taskmasters would relax vigilance by reason of some counter-interest. Who but their immediate guard could have instant knowledge that two aeroplanes in the common run were carrying other than real “defenders of the faith” on scouting journey?

And if all of these intimates in a bunch should join one of the daily processions to the mosques, some special occasion demanding it, “just see us get,” as Billy said when figuring on such a happening.

It came about that on a memorable day, nearing sunset, and the return of the Turkish airmen from various scouting tours anticipated, the four captives found themselves alone in the makeshift aerodrome.

“Catch on here,” was Billy’s quick summons to the others, who as quickly responded in rolling out the war-planes and into the starting place at the rear of the barracks.

The boy pilots set the motors in motion, and never had the buzzing seemed louder nor more insistent for attention than on this occasion, when every nerve in the four human make-ups was taut and tense with suppressed excitement.

They are off! Rising above that remarkable square of At-Meidan, occupying the site of the ancient Hippodrome, and wheeling to the right of the magnificent mosque of Soliman, the young aviators had a clear view of the sea-front.

Coming in both directions, up and down the coast, were the six or eight Turkish aircraft that had set out from the capital several hours previous.