David went quietly upstairs. It was just possible that the murderer was in the house. But the closest search brought nothing to light. He pulled out the jewel-drawer in the dressing-table. The spare latchkey had gone! Here was something to go upon.
Then there was a rumbling of an electric bell somewhere that set David’s heart beating like a drum. The hall light streamed on a policeman in uniform and an inspector in a dark overcoat and a hard felt hat. On the pavement was a long shallow tray, which David recognised mechanically as the ambulance.
“Something very serious, sir?” Inspector Marley asked, quietly. “I’ve brought the doctor with me.”
David nodded. Both the inspector and the doctor were acquaintances of his. He closed the door and led the way into the study. Just inside the conservatory and not far from the huddled figure lay David’s new cigar-case. Doubtless, without knowing it, the owner had whisked it off the table when he had sprung the telephone.
“‘Um,” Marley muttered. “Is this a clue, or yours, sir?”
He lifted the case with its diamonds gleaming like stars on a dark night. David had forgotten all about it for the time, had forgotten where it came from, or that it contained £250 in bank-notes.
“Not mine,” he said. “I mean to say, of course, it is mine. A recent present. The shock of this discovery has deprived me of my senses pretty well.”
Marley laid the cigar-case on the table. It seemed strange to him, who could follow a tragedy calmly, that a man should forget his own property. Meanwhile Cross was bending over the body. David could see a face smooth like that of a woman. A quick little exclamation came from the doctor.
“A drop of brandy here, and quick as possible,” he commanded.
“You don’t mean to say,” Steel began; “you don’t—”
Cross waved his arm, impatiently. The brandy was procured as speedily as possible. Steel, watching intently, fancied that he detected a slight flicker of the muscles of the white, stark face.
“Bring the ambulance here,” Cross said, curtly. “If we can get this poor chap to the hospital there is just a chance for him. Fortunately, we have not many yards to go.”
As far as elucidation went Marley naturally looked to Steel.
“I should like to have your explanation, sir,” he said, gravely.
“Positively, I have no explanation to offer,” David replied. “About midnight I let myself out to go for a stroll, carefully closing the door behind me. Naturally, the door was on the latch. When I came back an hour or so later, to my horror and surprise I found those marks of a struggle yonder and that poor fellow lying on the floor of the conservatory.”
“‘Um. Was the door fast on your return?”
“No, it was pulled to, but it was open all the same.”
“You didn’t happen to lose your latch-key during your midnight stroll, sir?”
“No, it was only when I put my key in the door that I discovered it to be open. I have a spare latch-key which I keep for emergencies, but when I went to look for it just now the key was not to be found. When I came back the house was perfectly quiet.”
“What family have you, sir? And what kind of servants?”
“There is only myself and my mother, with three maids. You may dismiss any suspicion of the servants from your mind at once. My mother trained them all in the old vicarage where I was born, and not one of the trio has been with us less than twelve years.”
“That simplifies matters somewhat,” Marley said, thoughtfully. “Apparently your latch-key was stolen by somebody who has made careful study of your habits. Do you generally go for late walks after your household has gone to bed, sir?”
David replied somewhat grudgingly that he had never done such a thing before. He would like to have concealed the fact, but it was bound to come out sooner or later. He had strolled along the front and round Brunswick Square. Marley shrugged his shoulders.
“Well, it’s a bit of a puzzle to me,” he admitted. “You go out for a midnight walk—a thing you have never done before—and when you come back you find somebody has got into your house by means of a stolen latch-key and murdered somebody else in your conservatory. According to that, two people must have entered the house.”
“That’s logic,” David admitted. “There can be no murder without the slain and the slayer. My impression is that somebody who knows the ways of the house watched me depart. Then he lured his victim in here under pretence that it was his own house—he had the purloined latch- key—and murdered him. Audacious, but a far safer way than doing it out of doors.”
But Marley’s imagination refused to go so far. The theory was plausible enough, he pointed out respectfully, if the assassin had been assured that these midnight rambles were a matter of custom. The point was a shrewd one, and Steel had to admit it. He almost wished now that he had suggested that he often took these midnight rambles. He regretted the fiction still more when Marley asked if he had had some appointment elsewhere to-night.
“No,” David said, promptly, “I hadn’t.”
He prevaricated without hesitation. His adventure in Brunswick Square could not possibly have anything to do with the tragedy, and nothing would be gained by betraying that trust.
“I’ll run round to the hospital and come and see you again in the morning, sir,” Marley said. “Whatever was the nature of the crime, it wasn’t robbery, or the criminal wouldn’t have left that cigar-case of yours behind. Sir James Lythem had one stolen like that at the last races, and he valued it at £80.”
“I’ll come as far as the hospital with you,” said Steel.
At the bottom of the flight of steps they encountered Dr. Cross and the policeman. The former handed over to Marley a pocket-book and some papers, together with a watch and chain.
“Everything that we could find upon him,” he explained.
“Is the poor fellow dead yet?” David asked.
“No,” Cross replied. “He was stabbed twice in the back in the region of the liver. I could not say for sure, but there is just a chance that he may recover. But one thing is pretty certain—it will be a good long time before he is in a position to say anything for himself. Good-night, Mr. Steel.”
David went indoors thoughtfully, with a general feeling that something like a hand had grasped his brain and was squeezing it like a sponge. He was free from his carking anxiety now, but it seemed to him that he was paying a heavy price for his liberty. Mechanically, he counted out the bank-notes, and almost as mechanically he cut his initials on the gun-metal inside the cigar-case. He was one of the kind of men who like to have their initials everywhere.
He snapped the lights out and went to bed at last. But not to sleep. The welcome dawn came at length and David took his bath gratefully. He would have to tell his mother what had happened, suppressing all reference to the Brunswick Square episode. It was not a pleasant story, but Mrs. Steel assimilated it at length over her early tea and toast.
“It might have been you, my dear,” she said,
