Desmond suddenly felt rather sick. This progress from one deed of violence to another revolted him. The others crowded into the cellar; but he did not follow them. He remained at the top of the trap, leaning against the wall, trying to collect his thoughts.

Barbara Mackwayte was now his sole preoccupation. If anything had happened to her,--it was through his fault alone; for he began to feel sure she must have come to the Mill House in his absence.

What then had become of her? The blood-stained toque pointed to foul play. But if they had murdered her, what had they done with the body?

His thoughts flew back to his interview with Nur-el-Din upstairs on the previous afternoon. He remembered the entrance of the maid and the dancer's hurried exit. Might not Marie have come to tell her that Barbara Mackwayte was below asking for her? It was very shortly after this interruption that, crouching on the roof of the shed, he had heard that m.u.f.fled cry from the house and seen Ra.s.s enter the bar and speak with Strangwise. He had seen, too, the maid, Marie, in earnest conversation with Strangwise by the back gate on the fen. Had both Marie and Ra.s.s been in league with Strangwise against the dancer? And had Nur-el-Din discovered their treachery? His mind refused to follow these deductions to their logical sequence; for, black as things looked against Nur-el-Din, he could not bring himself to believe her a murderess.

But now there were footsteps on the ladder. They were all coming out of the cellar again. As soon as Francis saw Desmond's face, he caught his brother by the arm and said:

"The open air for you, my boy! You look as if you'd seen a ghost!

I should have remembered all you've gone through!"

He walked him quickly through the tap-room and out through the inn door into the yard.

The rain had ceased and the sun was making a brave attempt to shine through the clouds. The cold air did Desmond good and after a turn or two in the yard, arm in arm with Francis, he felt considerably better.

"Where is Miss Mackwayte?" he asked.

"Des," said his brother, "I don't know and I don't want to cross-examine Nur-el-Din in there until I have reasoned out some theory which will fit Miss Mackwayte in her place in this horrible affair. The men have gone to search the outhouses and precincts of the inn to see if they can find any traces of her body, but I don't think they will find anything. I believe that Miss Mackwayte is alive."

"Alive?" said Desmond.

"The blood on that toque of hers might have been Ra.s.s's. There is a good deal of blood on the floor. You see, I still think Miss Mackwayte's safety depends on that jewel not being recovered by either Strangwise or Nur-el-Din. Strangwise, we know, has lost the jewel and there is no trace of it here: moreover, we know that, as late as yesterday afternoon, Nur-el-Din did not have it.

Therefore, she cannot have sent it away! I am inclined to believe, too, that Strangwise, before going over to the Mill House last night, carried off Miss Mackwayte somewhere with the aid of Ra.s.s and Marie, who were evidently his accomplices, in order to find out from her where the jewel is concealed..."

"But Miss Mackwayte cannot know what has become of it," objected Desmond.

"Maybe not," retorted his brother, "but both Strangwise and Nur-el-Din know that the jewel was originally entrusted to her charge. Nur-el-Din did not, it is true, tell Miss Mackwayte what the silver box contained but the latter may have found out, at least the dancer might suppose so; while Strangwise might think the same. Therefore, both Strangwise and Nur-el-Din had an interest in detaining Miss Mackwayte, and I think Strangwise forestalled the dancer. When Nur-el-Din discovered it, both Ra.s.s and her maid paid the penalty of their betrayal."

They walked once up and down the yard before Desmond replied.

"Francis," he said, "you remember Nur-el-Din's story--I told it to you just as I had it from her."

"Perfectly," answered his brother.

"Well," Desmond went on deliberately, "I think that story gives us the right measure of Nur-el-Din's, character. She may be vain, she may be without morals, she may be weak, she may be an adventuress, but she's not a murderess. If anything, she's a victim!"

Francis laughed shortly.

"Victim be d.a.m.ned!" he cried. "Man alive," he went on, "how can you talk such nonsense in face of the evidence, with this b.l.o.o.d.y-minded woman's victims hardly cold yet? But, horrible as these murders are, the private squabbles of this gang of spies represent neither your interest nor mine in this case. For us the fact remains that Nur-el-Din, besides being a monster of iniquity, is the heart and soul and vitals of the whole conspiracy!"

Jaded and nervous, Desmond felt a quick sting of resentment at his brother's tone. Why should Francis thus lay down the law to him about Nur-el-Din? Francis knew nothing of the girl or her antecedents while he, Desmond, flattered himself that he had at least located the place she occupied in this dark conspiracy. And he cried out vehemently:

"You're talking like a fool! I grant you that Nur-el-Din has been mixed up with this spy crowd; but she herself stands absolutely apart from the organization..."

"Half a minute!" put in Francis, "aren't you forgetting that blue envelope we took off her just now?"

"What about it?" asked Desmond sharply.

"Merely this; the cipher is in five figure groups, addressed to a four figure group and signed by a six figure group..."

"Well?"

"That happens to be the current secret code of the German Great General Staff. If you were to tap a German staff message out in France to-day, ten to one it would be in that code. Curious coincidence, isn't it?"

When one is angry, to be baffled in argument does not have a sedative effect as a rule. If we were all philosophers it might; but being merely human beings, cold reason acts on the inflamed temperament as a red rag is said to affect a bull.

Desmond, sick with the sense of failure and his anxiety about Barbara, was in no mood to listen to reason. The cold logic of his brother infuriated him mainly because Desmond knew that Francis was right.

"I don't care a d.a.m.n for the evidence," vociferated Desmond; "It may look black against Nur-el-Din; I daresay it does; but I have met and talked to this girl and I tell you again that she is not a princ.i.p.al in this affair but a victim!"

"You talk as if you were in love with the woman!" Francis said mockingly.

Desmond went rather white.

"If pity is a form of love," he replied in a low voice, "then I am, for G.o.d knows I never pitied any woman as I pity Nur-el-Din!

Only you, I suppose," he added bitterly, "are too much of the policeman, Francis, to appreciate anything like that!" Hot tempers run in families and Francis flared up on the instant.

"I may be a policeman, as you say," he retorted, "but I've got enough sense of my duty, I hope, not to allow sentimentality to interfere with my orders!"

It was a shrewd thrust and it caught Desmond on the raw.

"I'm sick of arguing here," he said hotly, "if you're so mighty clever, you'd better shoot Nur-el-Din first and arrest Strangwise afterwards. Then you'll find out which of us two is right!"

He turned on his heel and started for the little bridge leading out onto the fen.

Francis stood still a moment watching him, then ran after him. He caught up with Desmond as the latter reached the bridge.

"Desmond!" he said, pleadingly.

"Oh, go to h.e.l.l!" retorted the other savagely, whereupon Francis turned his back on him and walked back to the inn.

A car had stopped by the bridge and a man was getting out of it as Desmond moved towards the fen. The next moment he found himself face to face with the Chief.

The Chief's face was hard and cold and stern. There was a furrow between his eyes which deepened when he recognized Desmond.

"Well," he said curtly, "and where is my secretary?"

"I don't know," Desmond faltered.

"Why are you here, then?" came back in that hard, uncompromising voice.

Desmond was about to reply; but the other checked him.

"I know all you have to say," he resumed, "but no excuse you can offer can explain away the disappearance of Miss Mackwayte. Your orders were formal to remain at home. You saw fit to disobey them and thereby, maybe, sent Miss Mackwayte to her death. No!" he added, seeing that Desmond was about to expostulate, "I want to hear nothing from you. However obscure the circ.u.mstances of Miss Mackwayte's disappearance may be, one fact is perfectly clear, namely, that she went to the Mill House, as she was ordered and you were not there. For no man or woman in my service ever dares to disobey an order I have given."

"Chief..." Desmond broke in, but again that inexorable voice interposed.

"I will hear nothing from you," said the Chief, "it is a rule of mine never to interfere with my men in their work or to see them until their mission has been successfully completed. When you have found Miss Mackwayte I will hear you but not before!"