“Well, I never saw such a fellow!” exclaimed Raynor. “For goodness’ sake forget your everlasting coherers and keys and converters and the rest of them and enjoy taking life easy. But—hullo!” he broke off, “there’s someone we know.”

Approaching them was a dapper little man, with a neat black moustache and dressed in a careful, almost dignified manner.

“Why, it’s Raymond de Garros, that French aviator we saved from the sea off Florida when we were on the old Tropic Queen!” exclaimed Jack.

“That’s the man. But what in the world is he doing here? I thought he was in France organizing an aeroplane corps for the army.”

“So did I. The newspapers have had several despatches about his work. But we shall soon find out about the reason for his being on board.”

A minute later they were warmly shaking hands with the little Frenchman, who, with many gesticulations and twirlings of his moustache, assured them how glad he was to “greet zee two brave boys zat save my life from zee sea.”

“You’re the last person we expected to see,” said Jack, when first greetings were over. “We didn’t even know you were in America.”

The little Frenchman shrugged his shoulders and looked about him uneasily. Then he buttonholed the boys confidentially.

“No one know zat I am here but my government,” he said in low tones.

“You are on a secret mission of some kind?” asked Jack.