f by a feeling of
amusement caused by the man's looks of wonder, stood fast while Sam
passed his handkerchief over the back of one hand and then drew back,
laughing softly.

"Well, Sam!" he cried.

"I say, sir, you do look rum! I shouldn't have known you. I don't know
you now, and I don't believe your own mother would."

"Then you think the disguise is perfect enough?"

"Disguise, sir? You can't call that a disguise! It's the real thing.
Why, you're a downright genuine nigger, that you are!"

"That's right, Sam," said Frank, smiling now.

"And the best of it is, sir, that you're regular fast colours."

"I hope so, Sam."

"Think you could bear to wash yourself, sir?"

"Oh, yes. It will take weeks to make this look lighter."

"Well, I call it amazing, sir. There ain't no need for you to mind
where you go. No dervish could take you for a white man, unless he was
mad. But am I to be painted that colour?"

"No; you will go as you are--the Hakim's white servant."

"Well, just as you like, sir; I don't mind. I'll be touched up like you
are if you think it will be safer for a man. It's wonderful, sir. And
no fear of its showing the dirt. But pst! here's some one coming. The
doctor and Mr Landon, sir. I thought you were sitting along with them.
Have they seen you like this?"

"No, Sam; I was just getting ready for them."

"Did they know it, sir?"

"No."

"Then I'll go in yonder. You stop and let 'em catch you sudden like.
Just to try if they'll know you."

Frank nodded, and Sam darted into the inner tent, just having
disappeared as the professor sauntered in with the doctor, and both drew
up short.

"Hullo, you, sir!" said the professor gruffly, in Arabic; "what business
have you here?"

Frank made no reply, but edged a little to one side, while at the same
moment the doctor caught sight of the clothes lying on the floor, and
uttered an exclamation.

"Yes, see!" cried the professor. "Robbers, eh? Help me, and we'll tie
this fellow up."

"Quick, then," said the doctor. "Look out for his knife. Bah! how
absurd!" he added the next moment, calming down from the excitability he
had displayed.

"What do you mean?" cried the professor sharply.

"Don't hold back. Why!--what!--My dear Frank, what a metamorphosis!"

"Yes," said Frank quietly. "I have passed muster with three of you, so
I suppose it will do."

"Do!" cried the professor. "Why, it is simply admirable. Stop a
minute, I