After a few steps he crossed his arms with a quick, peculiar movement and drew from under his armpits the pair of automatic pistols.

Like all “forested” forests, the woods on that flank of Mount Terrible were regular and open—­big trees with no underbrush and a smooth carpet of needles and leaves under foot.  And Recklow now walked on very fast in the dim light until he came to a thinning among the trees where just ahead of him, stars shimmered level in the vast sky-gulf above Alsace.

Here was the precipice; here the narrow, wooded neck—­the only way across the mountain except by the peak path and the Crucifix.

Now Recklow took from his pockets his spool of very fine wire, attached it low down to a slim young pine, carried it across to the edge of the cliff, and attached the other end to a sapling on the edge of the ledge.  On this wire he hung his cowbell and hooked the little clapper inside.

Then, squatting down on the pine needles, he sat motionless as one of the forest shadows, a pistol in either hand, and his cold grey eyes ablaze.

So silvery the pools of light from the planets, so depthless the shadows, that the forest around him seemed but a vast mosaic in mother-of-pearl and ebony.

There was no sound, no murmur of cattle-bells from mountain pastures now, nothing stirring through the magic aisles where the matched columns of beech and pine towered in the perfect symmetry of all planted forests.

He had not been there very long; the luminous dial of his wrist-watch told him that—­when, although he had heard no sound on the soft carpet of pine needles, something suddenly hit the wire and the cowbell tinkled in the darkness.

Recklow was on his feet in an instant and running south along the wire.  It might have been a deer crossing to the eastern slope; it might have been the enemy; he could not tell; he could see nothing stirring.  And there seemed to be nothing for him to do but to take his chances.

“McKay!” he called in a low voice.

Then, amid the checkered pools of light and shade among the trees a shadow moved.

“McKay!  It’s Number Seventy.  If it’s you, call out your number, because I’ve got you over my sights and I shoot straight!”

“Seventy-six and Seventy-seven!” came McKay’s cautious voice.  “Good heavens, Recklow, why have you come up here?”

“Don’t touch the wire again,” Recklow warned him.  “Drop flat both of you, and crawl under!  Crawl toward my voice!”

As he spoke he came toward them; and they rose from their knees among the shadows, pistols drawn.

“There’s been some dirty business,” said Recklow briefly.  “Three enemy spies went over the Swiss wire about an hour after you left Delle.  There are half a dozen Boches on the peak by the Crucifix.  And that’s why I’m here, if you want to know.”

There was a silence.  Recklow looked hard at McKay, then at Evelyn Erith, who was standing quietly beside him.