“Thanks,” said Rex briefly. “You can keep the Volga for me. I’d rather take a look at a plate of my favourite breakfast food.”

“Tomorrow, if our luck holds, you may!” De Richleau studied the map again. “Do you know that we are already half-way — we have done over eight hundred miles!”

“That a fact?” Rex brightened. “If so, we’ll make it; we haven’t used half the petrol yet”

The Duke was overjoyed. He went into the cabin to tell the others the good news. The morning light had just awakened them.

Simon, who had slept well and was looking considerably better, was surprised that it was so early, but De Richleau explained that they were now far to the south of Moscow — somewhere about the latitude of Birmingham, perhaps — by noon they might be as far south as the Channel Islands.

Poor Marie Lou looked very woebegone; she was shockingly pale, with great dark circles under her eyes. During the earlier part of the night she had been terribly airsick. De Richleau insisted that she should sit out in the rear cockpit with Simon — she would feel better in the air. When he had installed them he returned to Rex and said:

“Would it not be possible for me to take over for a little? You seem to sit there doing nothing!”

“Just what I was thinking,” Rex nodded. “A kid can fly an aeroplane these days once it’s off the ground. I’ll take her up another couple of thousand; then, if you do slip a thousand there’s no harm done.” He began to climb sharply.

The Duke settled himself comfortably at the second set of controls. “I was watching you last night,” he said. “I think I understand the principle of the thing.”

Rex laughed. “I wouldn’t have let you handle her over mountains; there’s air-pockets and every kind of snag, due to the uneven ground — but you’ll not get that here. Looks as though this plain goes on for ever — it should be dead easy.”