So saying, he drew his companion along toward a group of rocks that rose upon one point of the island; there, after searching for some time, he began to rummage among the brambles, and, in so doing, scratched his hands until they bled.

Suddenly he grasped Kennedy’s arm, exclaiming: “Look! look!”

“Letters!”

Yes; there, indeed, could be descried, with perfect precision of outline, some letters carved on the rock. It was quite easy to make them out:

“A. D.”

“A.D.!” repeated Dr. Ferguson. “Andrea Debono—the very signature of the traveller who farthest ascended the current of the Nile.”

“No doubt of that, friend Samuel,” assented Kennedy.

“Are you now convinced?”

“It is the Nile! We cannot entertain a doubt on that score now,” was the reply.

The doctor, for the last time, examined those precious initials, the exact form and size of which he carefully noted.