Suddenly as he rounded a large island he saw what for the moment he imagined to be a line of white surf, but the next instant he recognised a solid mass, as it were, of swallows and martins flying just over the surface of the water straight towards him.

He had no time to notice how far they extended before they had gone by him with a rushing sound.

Turning to look back, he saw them continue directly west in the teeth of the wind.
Like the water and the islands, the sky was now cleared of birds, and not a swallow remained.

Felix asked himself if he were running into some unknown danger, but he could not conceive any.

The only thing that occurred to him was the possibility of the wind rising to a hurricane; that gave him no alarm, because the numerous islands would afford shelter.