“Jawohl!” he answered in a perfectly emotionless voice.

And then he smiled and in a flash the old Francis stood before me.

“Not a word now,” he said in German as he cleared away the breakfast.  “I am off this afternoon.  Meet me on the river promenade by the Schiller statue at a quarter past two and we’ll go for a walk.  Don’t stay here now but come back and lunch in the restaurant ... it’s always crowded and pretty safe!”

Then he called out into the void: 

“Twenty-six wants to pay!”

Such was my meeting with my brother.

CHAPTER XVI

A HAND-CLASP BY THE RHINE

That afternoon Francis and I walked out along the banks of the swiftly flowing Rhine until we were far beyond the city.  Anxious though I was that he should reveal to me that part of his life which lay hidden beneath those lines of suffering in his face, he made me tell my story first.  So I unfolded to him the extraordinary series of adventures that had befallen me since the night I had blundered upon the trail of a great secret in that evil hotel at Rotterdam.

Francis did not once interrupt the flow of my narrative.  He listened with the most tense interest but with a growing concern which betrayed itself clearly on his face.  At the end of my story, I silently handed to him the half of the stolen letter I had seized from Clubfoot at the Hotel Esplanade.

“Keep it, Francis,” I said.  “It’s safer with a respectable waiter like you than with a hunted outcast like myself!”

My brother smiled wanly, but his face assumed the look of grave anxiety with which he had heard my tale.  He scrutinized the slips of paper very closely, then tucked them away in a letter-case, which he buttoned up in his hip pocket.

“Fortune is a strange goddess, Des,” he said, his weary eyes roving out over the turgid, yellow stream, “and she has been kind to you, though, God knows, you have played a man’s part in all this.  She has placed in your possession something for which at least five men have died in vain, something that has filled my thoughts, sleeping and waking, for more than half a year.  What you have told me throws a good deal of light upon the mystery which I came to this cursed country to elucidate, but it also deepens the darkness which still envelops many points in the affair.

“You know there are issues in this game of ours, old man, that stand even higher than the confidence that there has always been between us two.  That is why I wrote to you so seldom out in France—­I could tell you nothing about my work:  that is one of the rules of our game.  But now you have broken into the scramble yourself, I feel that we are partners, so I will tell you all I know.

“Listen, then.  Some time about the beginning of the year a letter written by a German interned at one of the camps in England was stopped by the Camp Censor.  This German went by the name of Schulte:  he was arrested at a house in Dalston the day after we declared war on Germany.  There was a good reason for this, for our friend Schulte—­we don’t know his real name—­was known to my Chief as one of the most daring and successful spies that ever operated in the British Isles.