The guide stared at Lewis, then at the stranger.

"The sea! What is the sea?"

"The sea," said Lewis, gravely, "is the ocean, the great water where ships sail."

"Bah!" said the guide. "More madness. How shall I guide him to the sea if I know not where it is? Tell him there is no sea."

One of the muleteers broke in.

"Indeed, there is a sea, but it is far, far away. It is thirty days away."

"And how do you go?" asked Lewis.

"I do not know. I only know that one must go to Joazeiro, and from there they say there is a road of iron that leads one to the sea."

"Joazeiro!" exclaimed the guide. "Ah, that is some sense. Joazeiro is a place. It is on the river. Petrolina is on this side, Joazeiro on that. As for this road of iron, hah!" He turned on the muleteer. "Thou, too, art mad."

The stranger listened to what Lewis had to say, then he drew out a map from his pocket, unfolded it, and spread it on the table. "A road of iron, eh? Well, let's see."