"It does. As the island is composed largely of basalt, and shows signs of volcanic action, there can be no doubt as to its origin. Thousands of years ago a mighty earthquake must have shot this and hundreds of other islands above the surface, and from the floor of the vast submarine plateau the coral builders are doing their work of making new ground."

"Shall we try to trace the course of this stream, then? Yadillah has a large knife, so that we can clear a path through the scrub."

"Well, there's no harm in attempting it. Yadillah, you black imp!"

"Yas, sahib."

"Cut a path for us through this stuff." The Arab attacked the undergrowth vigorously, and, working as he went, disappeared in the tunnel that he had cut above the stream. Presently he returned with the information that the thicket extended only a short way, and that the brook ran through a dense coco-nut grove.

"Lead on, then, Yadillah," exclaimed the doctor. "You follow, Reggie, and I'll bring up the rear."

"Clear off, you niggers," he added, speaking authoritatively to the natives, who were regarding our movements with ill-concealed excitement. The doctor's words and actions had the desired effect, for the crowd of followers stood back, jabbering incessantly, save a few who made off towards the village.

Although we kept our thick water-tight boots on, the water was deliciously cool as we waded down the stream, bending low to escape the rough tendrils that overhung the low tunnel that the Arab had cut for us. A few steps brought us to the other side of the vegetable barrier, and, as Yadillah had said, the brook flowed through a fairly dense palm-grove, its bed being composed of hard, slippery rock.

After we had proceeded a few hundred yards the doctor suddenly exclaimed—

"Hullo! This looks interesting. There's a well-worn path here. I suppose it leads to the village."