'You've the wrong notion of romance,' I said. 'Why, man, last
night for an hour you were in the front line - the place where the
enemy forces touch our own. You were over the top - you were in
No-man's-land.'

He laughed. 'That is one way to look at it'; and then he stalked
off and I watched his lean figure till it was round the turn of the hill.

All that morning I smoked peacefully by the burn, and let my
thoughts wander over the whole business. I had got precisely what
Blenkiron wanted, a post office for the enemy. It would need
careful handling, but I could see the juiciest lies passing that way to
the _Grosses _Haupiquartier. Yet I had an ugly feeling at the back of
my head that it had been all too easy, and that Ivery was not the
man to be duped in this way for long. That set me thinking about
the queer talk on the crevice. The poetry stuff I dismissed as the
ordinary password, probably changed every time. But who were
Chelius and Bommaerts, and what in the name of goodness were the
Wild Birds and the Cage Birds? Twice in the past three years I had
had two such riddles to solve - Scudder's scribble in his pocket-
book, and Harry Bullivant's three words. I remembered how it
had only been by constant chewing at them that I had got a sort of
meaning, and I wondered if fate would some day expound this
puzzle also.

Meantime I had to get back to London as inconspicuously as I
had come. It might take some doing, for the police who had been
active in Morvern might be still on the track, and it was essential
that I should keep out of trouble and give no hint to Gresson and