A dark night in that part of French Flanders becomes palpably black during a few seconds after a flare. The Englishmen squatted back on their heels. Neither drew his revolver, but each right hand clutched a trench knife, a peculiarly murderous-looking implement with an oval handle, and shaped like a corkscrew, except that the screw is replaced by a short, flat, dagger-pointed blade. No signal was needed. Each knew exactly what to do. The accident of position allotted the major to Martin.

The Germans came on stealthily. They had noted the sh.e.l.l-hole, and sat on its crumbling edge, meaning to slide down and creep out on the other side. Martin's left hand gripped a stout boot by the ankle. In the fifth of a second he had a heavy body twisted violently and flung face down in the loose earth at the bottom of the hole. A knee was planted in the small of the prisoner's back, the point of the knife was under his right ear, and Martin was saying, in quite understandable German:

"If you move or speak, I'll cut your throat!"

The words have a brutal sound, but it does not pay to be squeamish on such occasions, and the German language adapts itself naturally to phrases of the kind.

Sergeant Mason had to solve his own problem by a different method. The quarry chanced to be leaning forward at the moment a vicious tug accelerated his progress. As a result, he fell on top of the hunter, and there was nothing for it but the knife. A ghastly squeal was barely stifled by the Englishman's hand over the victim's mouth. At thirty yards, or thereabouts, and coming from a deep hole, the noise might have been a grunt. Nevertheless, it reached the German trench.

"Wer da?" hissed a voice, and Martin heard the click of a machine-gun as it swung on its tripod.

He did not fear the gun, which only meant a period of waiting while its bullets cracked overhead. What he did dread was a search party, as German majors are valuable birds, and must be safeguarded. The situation called for the desperate measure he took. The point of the knife entered his captive's neck, and he whispered:

"Tell your men they must keep quiet, or you die now!"

He allowed the almost choking man to raise his head. The German knew that his life was forfeit if he did not obey the order. A certain gurgling, ever growing weaker, showed that his companion would soon be a corpse.

"Shut up, sheep's head!" he growled.

It sufficed. That is the way German majors talk to their inferiors.

The engineer sergeant wriggled nearer.

"Couldn't help it, sir," he breathed. "I had to give him one!"

"Go through him for papers and bring me his belt."

Within a minute the officer's hands were fastened behind his back. Then he was permitted to rise and, after being duly warned, told to accompany Mason. Martin followed, and the three began the return journey. A German rocket bothered them once, but the German was quick as they to fall flat. Evidently he was not minded to offer a target for marksmen on either side.

Soon Mason was sent forward to warn the sentries. Quarter of an hour after the episode in the sh.e.l.l hole Martin, having come from the telephone, was examining his prisoner by the light of an electric torch in a dugout.

"What is your name?" he inquired.

"Freiherr Georg von Struben, major of artillery," was the somewhat grandiloquent answer.

"Do you speak English?"

"Nod mooch."

Some long dormant chord of memory vibrated in Martin's brain. He held the torch closer. Von Struben was a tall, well-built Prussian. He smiled, meaning probably to make the best of a bad business. His face was soiled with clay and perspiration. A streak of blood had run from a slight cut over an eyebrow. But the white scar of an old saber wound, the outcome of a duelling bout in some university _burschenschaft_, creased down its center when he smiled. Then Martin knew.

"Fritz Bauer!" he cried.

The German started, though he recovered his self-control promptly.

"You haf nod unterstant," he said. "I dell you my nem----"

"That's all right, Fritz," laughed Martin. "You spoke good English when you were in Elmsdale. You could fool me then into giving you valuable information for your precious scheme of invading England. Now it's my turn! Have you forgotten Martin Bolland?"

Blank incredulity yielded to evident fear in the other man's eyes. With obvious effort, he stiffened.

"I was acting under orders, Captain Bolland," he said.

"Not Bolland, but Grant," laughed Martin. "I, too, have changed my name, but for a more honorable reason."

The words seemed to irritate von Struben.

"I did noding dishonorable," he protested. "I was dere by command. If it wasn't for your d--d fleet, I would have lodged once more in de Elms eighdeen monds ago."

"I know," said Martin. "We found your map, the map which Angle stole because you wouldn't take her in the car the day we went on the moor."

In all likelihood the prisoner's nerves were on edge. He had gone through a good deal since being hauled into the sh.e.l.l hole, and was by no means prepared for this display of intimate knowledge of his past career by the youthful looking Briton who had manhandled him so effectually. Be that as it may, he was so disconcerted by the mere allusion to Angle that a fantastic notion gripped Martin. He pursued it at once.

"We English are not quite such idiots as you like to imagine us, major,"

he went on, and so ready was his speech that the pause was hardly perceptible. "Mrs. Saumarez--or, describing her by her other name, the Baroness von Edelstein--was a far more dangerous person than you. It took time to run her to earth--you know what that means? when a fox is chased to a burrow by hounds--but our Intelligence Department sized her up correctly at last."

Now this was nothing more than the wildest guessing, a product of many a long talk with Elsie, the vicar, and General Grant during the early days of the war. But von Struben was manifestly so ill at ease that he had to cover his discomfiture under a frown.

"I have not seen de lady for ten years," he said.

This disclaimer was needless. He had been wiser to have cursed Angle for purloining his map.

"Perhaps not. She avoided Berlin. But you have heard of her."

Again was the former spy guilty of stupidity. He set his lips like a steel trap. Doubtful what to say, he said nothing.

Martin nodded to Sergeant Mason.

"Just go through the major's pockets," he said. "You know what we want."

Mason's knowledge was precise. He left the prisoner his money, watch, pipe, and handkerchief. The remainder of his belongings were made up into a bundle. Highly valuable treasure-trove was contained therein, the major having in his possession a detailed list of all arms in the Fifty-seventh Brandenburg Division and a sketch of the trench system which it occupied. A glance showed Martin that the Fifty-seventh Division lay directly in front.

He turned to the subaltern whose dugout he was using and who had witnessed the foregoing scene in silence.

"Can you send a corporal's guard to D.H.Q. in charge of the prisoner?"

he asked.

"Certainly," said the other. "By the way, come outside and have a cigarette."

Cigarettes are not lighted in front-line communication trenches after nightfall--not by officers, at any rate--nor do second lieutenants address staff captains so flippantly. Martin read something more into the invitation than appeared on the surface. He was right.

"About this Mrs. Saumarez you spoke of just now," said the subaltern when they were beyond the closed door of the dugout. "Is she the widow of one of our fellows, a Hussar colonel?"

"Yes."

"Do you know she is living in Paris?"

"Well, I heard some few years since that she was residing there."