Turk and the Persian wouldn't follow the ordinary new theology
game. He must be of the Blood. Your Mahdis and Mullahs and
Imams were nobodies, but they had only a local prestige. To capture
all Islam - and I gather that is what we fear - the man must be of
the Koreish, the tribe of the Prophet himself.'

'But how could any impostor prove that? For I suppose he's an
impostor.'

'He would have to combine a lot of claims. His descent must be
pretty good to begin with, and there are families, remember, that
claim the Koreish blood. Then he'd have to be rather a wonder on
his own account - saintly, eloquent, and that sort of thing. And I
expect he'd have to show a sign, though what that could be I
haven't a notion.'

'You know the East about as well as any living man. Do you
think that kind of thing is possible?' I asked.

'Perfectly,' said Sandy, with a grave face.

'Well, there's the ground cleared to begin with. Then there's the
evidence of pretty well every secret agent we possess. That all
seems to prove the fact. But we have no details and no clues except
that bit of paper.' I told them the story of it.

Sandy studied it with wrinkled brows. 'It beats me. But it may be
the key for all that. A clue may be dumb in London and shout
aloud at Baghdad.'