ing Narkom's query, as they whizzed home through the darkness together by the last up train that night. "Simplest thing in the world. As you know, the 5.28 from London Bridge runs without stop to Anerley. Well, the 5.18 from the same starting-point runs to the Crystal Palace Low Level, taking the main line tracks as far as Sydenham, where it branches off at the switch and curves away in an opposite direction. That is to
say, for a considerable distance they run parallel, but eventually diverge.
"Now, as the 5.18 is a train with several stops, the 5.28, being a through one, overtakes her, and several times between Brockley and Sydenham they run side by side, at so steady a pace and on such narrow gauge that the footboard running along the side of the one train is not more than two and a half feet separated from the other. Their pace is so regular, their progress so even, that one could with ease step from the footboard of the one to the footboard of the other but for the horrible suction which would inevitably draw the person attempting it down under the wheels.
"Well, something had to be devised to overcome the danger of that suction. But what? I asked myself, for I guessed from the first how the escape had occurred, and I knew that such a thing absolutely required the assistance of a confederate. That meant that the confederate would have to do, on the 5.18, exactly what they had trapped Stavornell into doing on the other train: that is, secure a private compartment, so that when the time came for the escape to be accomplished he could remove the electric bulbs from the roof of his compartment, open the door, and, when the two came abreast, the assassin could do the same on the other train, and presto! the dead man would be alone. But what to use to overcome the danger of that horrible suction?"
"Ah, I see now what you were driving at when you
inquired about the ironing-board or the Indian canoe. The necessary sections to construct a sort of bridge could be packed in either?"
"Yes. But they chose a simple plan, the cutting-table. A good move that. Its breadth minimised the peril of the suction; only, of course, it would have to be pulled up afterward, to leave no clue, and the added space would call for enormous strength to overcome the power of that suction; and enormous strength meant a powerful man. The rest you can put together without being told, Mr. Narkom. When that little vixen finished her man, she put out the lights, opened the door (deliberately locking it after her to make the thing more baffling), crossed over on that table, was helped into the other compartment by Murchison, and then as expeditiously as possible slipped on the loose feminine outer garments she carried with her in the brown portmanteau, the table was hauled up and taken in—nothing but wire rope for that, sir—and the thing was done.
"Murchison, of course, purchased two tickets, so that they might pass the barrier at the Low Level unquestioned when they left, but he wasn't able to get the extra ticket clipped at London Bridge because there was no passenger for it. That's how I got on to the little game! For the rest, they planned well. Those two trains being always packed, nobody could see the escape from the one to the other, because people would be standing up in every compartment, and the windows completely blocked. But if—— Hullo! Victoria at last, thank goodness, 'and so to bed,' as Pepys says. The riddle's solved, Mr. Narkom. Good-night!"