'But ... but -' I did not know how to put it, and stammered in
my eagerness. 'How can I tell that you are the right person for me
to speak to? You see I am under orders, and I have got none
about you.'

'I will give You Proof,' she said. 'Three days ago Sir Walter
Bullivant and Mr Macgillivray told you to come here tonight and
to wait here for further instructions. You met them in the little
smoking-room at the back of the Rota Club. You were bidden take
the name of Cornelius Brand, and turn yourself from a successful
general into a pacifist South African engineer. Is that correct?'

'Perfectly.'

'You have been restless all evening looking for the messenger to
give you these instructions. Set your mind at ease. No messenger is
coming. You will get your orders from me.'

'I could not take them from a more welcome source,' I said.

'Very prettily put. If you want further credentials I can tell you
much about your own doings in the past three years. I can explain
to you who don't need the explanation, every step in the business
of the Black Stone. I think I could draw a pretty accurate map of
your journey to Erzerum. You have a letter from Peter Pienaar in
your pocket - I can tell you its contents. Are you willing to trust
me?'

'With all my heart,' I said.