duodenum.'

I was listening with a quickened pulse, for now at last I was
getting to business.

'What is he - international socialist, or anarchist, or what?'
I asked.

'Pure-blooded Boche agent, but the biggest-sized brand in the
catalogue - bigger than Steinmeier or old Bismarck's Staubier.
Thank God I've got him located ... I must put you wise about
some things.'

He lay back in his rubbed leather armchair and yarned for twenty
minutes. He told me how at the beginning of the war Scotland Yard
had had a pretty complete register of enemy spies, and without
making any fuss had just tidied them away. After that, the covey
having been broken up, it was a question of picking off stray birds.
That had taken some doing. There had been all kinds of inflammatory
stuff around, Red Masons and international anarchists, and, worst of
all, international finance-touts, but they had mostly been ordinary
cranks and rogues, the tools of the Boche agents rather than agents
themselves. However, by the middle Of 1915 most of the stragglers
had been gathered in. But there remained loose ends, and towards
the close of last year somebody was very busy combining these ends
into a net. Funny cases cropped up of the leakage of vital information.
They began to be bad about October 1916, when the Hun submarines
started on a special racket. The enemy suddenly appeared possessed
of a knowledge which we thought to be shared only by half a dozen
officers. Blenkiron said he was not surprised at the leakage, for