Some chance effect produced by the shadow of the moonlight, and the presence of that recently purchased ticket, gave me the idea upon which without delay I proceeded to act. Satisfying myself that there was no mark upon any of his garments by which the man could be identified, I unlocked from my wrist an identification disk which I habitually wore there, and locked it upon the wrist of the man with the scar!

Clearly, I argued, he had been detailed to dispatch me and then to leave at once for France. I would make it appear that he had succeeded.

Behold me, ten minutes later, driving slowly along a part of the Thames Embankment which I chanced to remember, a gruesome passenger riding behind me in the cab. I was reflecting as I kept a sharp look-out for a spot which I had noted one day during my travels, how easily one could commit murder in London, when a constable ran out and intercepted me!

Mon Deiu! how my heart leapt!

"I'll trouble you for your name and number, my lad," he said.

"What for?" I asked, and remembering a rare fragment of idiom: "What's up with you?" I added.

"Your lamp's out!" he cried, "that's what's up with me!"

"Oh," said I, climbing from my seat—"very well. I'm sorry. I didn't know. But here is my license."

I handed him the little booklet and began to light my lamps, cursing myself for a dreadful artist because I had forgotten to do so.

"All right," he replied, and handed it back to me. "But how the devil you've managed to get all your lamps out, I can't imagine!"