ied hard. No one really does know except
the chief. Some say we are going to Omdurman, while others say for
certain that we shall make a sweep round into the desert and then aim
for Khartoum. While others--"

"Opinions are various," said the professor drily. "_Tot homines_--_tot
sententiae_, which being interpreted, my dear Frank, you being a lad who
always hated your Latin accidence, means, some think a tot of one thing
is good; some think a tot of another is better. Well, Ibrahim, what
does the other set think?"

"That the chief is going straight to Omdurman before passing on to
Khartoum to dispose of his plunder."

"Then let's hope the last are right, and then we shall have the chance
of searching two places. There, cheer up, Frank, and try and think of
nothing else but our own important mission."

"Of course," said the doctor. "We did not come for the purpose of
punishing these predatory hordes."

"No," said Frank sadly; "I know. But have a little compassion upon me,
and forgive my irritable ways. Look at me," he said, holding out his
blackened hands, and then pointing with them to his face. "Can't you
think how great an effort it is to keep up this miserable masquerade--
what agony it is to go about feeling that at any moment I may forget
myself when in the presence of our masters, and speak?"

"Yes, yes, I know, Frank, my dear boy," replied the professor; "and
whenever I think of it I begin to wonder. I used to be in a constant
state of fidget. `He'll let the cat out of the bag as sure as eggs are
eggs,' I used to say to myself; and then I lay awake at night and tried
to think out the best way of helping you till the idea came, and it has
acted beautifully."

"What idea?" said the doctor sternly. "You never mentioned any idea to
me."

"Of course not; that would have spoiled the charm. Even Frank does not
know."

"Then it's all nonsense," said the doctor.

"Is it? Well, we'll see. I did help you, didn't I, Frank?"

"You have always helped me in every way you could, and been like an
elder brother towards me, and I can never be sufficiently grateful."

"Bother! Nonsense!" said the professor curtly. "But you mean to say I
did not specially help you over the dummy business?"

"Well, I really cannot recollect any special way."

"Ingrate! And you talk about being grateful."

"Well, out with it, Fred," said the doctor. "What was your plan?"

"One of my own invention," said the profe