When they were well over five thousand feet Rex took his hand off the controls. “All you’ve got to do,” he shouted, “is to keep her steady, keep your eye on the indicator, and look at the compass needle now and again.”
For some minutes he sat watching the Duke’s first efforts as a pilot. They bumped a little owing to De Richleau’s eagerness to correct their altitude too quickly, but his long sensitive fingers soon found the right touch.
“You’ll do,” said Rex, yawning again. “If the ground gets broken, wake me; if anything goes wrong, you’re not the sort of man I’d insult by telling not to panic — but for God’s sake take your hands off the controls. Just give me one kick and drop ’em. Don’t attempt to right her; leave that to me. I’ll have her under control again long before we could crash at this height, even if she’s in a falling spin.” Next moment he was asleep.
The distant plain stretched out interminably. With practice the Duke soon grew more proficient. He would have liked to have tried a few experiments, but would not allow himself to be tempted into taking any risks.
The morning wore on, the ground below changed to long rolling slopes of grassland, the seemingly endless steppes of Russia. At a little after eleven they passed another great river, which De Richleau thought to be the Don. He woke Rex in order to make certain.
Rex, still yawning, but much fresher, took over the controls again, and the Duke consulted his map. Yes, it was the Don — their progress had been wonderful. They were now about three hundred miles south of Moscow, another four hundred and fifty miles would bring them to the frontier of Roumania, it really seemed that they might get through in this one tremendous headlong flight. All of them, except Marie Lou, felt in urgent need of food — the lockers in the cabin had been searched and found to contain nothing edible.
Just after midday they left a city that the Duke declared to be Kursk on their right. Their hopes rose more strongly than ever, for far below them lay the frontier of the Ukraine; at least, they were out of Russia proper.
The ’plane bored on to the west through the sharp, crisp air. With perfect rhythm the engines droned on over their heads. Rex was enchanted with the machine. For some time he had been puzzling about the mechanism of the helicopter. It was unlike any that he had ever seen, having two blades only instead of four. At last he solved the problem to his satisfaction and turned to the Duke.
“Cute dodge, that helicopter. When it’s not in action it forms another ’plane above our heads, both blades in alignment with the wings. They answer, too, at the same time to the controls. If you’re going to use it on its own, the right-hand blade turns completely over, so that the thin edge of both spins in the same direction when it revolves. Guess I’ll patent that when I get home!”
De Richleau looked up — it was true. Instead of four blades at an angle impeding the flying speed, and useless except for going up or coming down, the helicopter formed a small but perfect extra ’plane which helped to carry the weight of the machine. As he looked, the Duke’s eyes narrowed, and his mouth set in a grim line. He had seen something in addition to the helicopter. Above, and to the right, hovered six ’planes flying in formation. He nudged Rex and pointed.