“He says that because he wants to make the best of it, but I’m not going to believe my poor guv’nor’s enjoying this. He’s wishing himself back in Wimpole Street, I know.”

“What’s that?” said Frank suddenly.

“What? I see nothing.”

“No, no. I mean that wild cry.”

“Only a jackal. I daresay if you listen you will hear another answer it. Pleasant note, isn’t it?”

“Horrible! It sounded like some poor creature in pain.”

“Hungry, perhaps,” said the professor coolly. “Fine, wild, weird prospect, this, eh?”

“It seems very dream-like and strange.”

“Yes, it impressed me like that at first. After a while you begin to think of how delightful it is, and what a change from pacing over the burning sand in the daylight with the sun making the air quiver and glow like a furnace, and your mouth turn dry and lips crack with the parching you have to undergo.”

“Shall we have to journey much by night?”