When he rose, the next morning, Rand noticed something which had escaped his eye when he had gone to bed the night before. His .38-special, in its shoulder-holster, was lying on the dresser; he had not bothered putting it on when he had gone to see Rivers the morning before, and it had lain there all the previous day. He distinctly remembered having moved it, shortly after dinner, when he had gone to his room for some notes he had made on the collection.  
However, between that time and the present it had managed to flop itself over; the holster was now lying back-up. Intrigued by such a remarkable accomplishment in an inanimate object, Rand crossed the room in the dress-of-nature in which he slept and looked more closely at it, receiving a second and considerably more severe surprise. The revolver in the holster was not his own.
 
It was, to be sure, a .38 Colt Detective Special, and it was in his holster, but it was not the Detective Special he had brought with him from New Belfast. His own gun was of the second type, with the corners rounded off the grip; this one was of the original issue, with the square Police Positive grip. His own gun had seen hard service; this one was in practically new condition. There was a discrepancy of about thirty thousand in the serial numbers. His gun had been loaded in six chambers with the standard 158-grain loads; this one was loaded in only five, with 148-grain mid-range wad-cutter loads.
 
Rand stood for some time looking at the revolver. The worst of it was that he couldn't be exactly sure when the substitution had been made. It might have happened at any time between eight o'clock and twelve, when he had gone to bed. He rather suspected that it had been accomplished while he had been in the bathroom, however.
 
Dumping out the five rounds in the cylinder, he inspected the changeling carefully. It was, he thought, the revolver Lane Fleming had kept in the drawer of the gunroom desk. There was no obstruction in the two-inch barrel, the weapon had not been either fired or cleaned recently, the firing-pin had not been shortened, the mainspring showed the proper amount of tension, and the mechanism functioned as it should. There was a chance that somebody had made up five special hand-loads for him, using nitroglycerin instead of powder, but that didn't seem likely, as it would not necessitate a switch of revolvers. There were four or five other possibilities, all of them disquieting; he would have been a great deal less alarmed if somebody had taken a shot at him.
 
Getting a box of cartridges out of his Gladstone, he filled the cylinder with 158-grain loads. When he went to the bathroom, he took the revolver in his dressing-gown pocket; when he dressed, he put on the shoulder-holster, and pocketed a handful of spare rounds.
 
Anton Varcek was loitering in the hall when he came out; he gave Rand good-morning, and fell into step with him as they went toward the stairway.
 
"Colonel Rand, I wish you wouldn't mention this to anybody, but I would like a private talk with you," the Czech said. "After Fred Dunmore has left for the plant. Would that be possible?"
 
"Yes, Mr. Varcek; I'll be in the gunroom all morning, working." They reached the bottom of the stairway, where Gladys was waiting. "Understand," Rand continued, "I never really studied biology. I was exposed to it, in school, but at that time I was preoccupied with the so-called social sciences."
 
Varcek took the conversational shift in stride. "Of course," he agreed. "But you are trained in the scientific method of thought. That, at least, is something. When I have opportunity to explain my ideas more fully, I believe you will be interested in my conclusions."
 
They greeted Gladys, and walked with her to the dining-room. As usual, Geraldine was absent; Dunmore and Nelda were already at the table, eating in silence. Both of them seemed self-conscious, after the pitched battle of the evening before. Rand broke the tension by offering Humphrey Goode in the role of whipping-boy; he had no sooner made a remark in derogation of the lawyer than Nelda and her husband broke into a duet of vituperation. In the end, everybody affected to agree that the whole unpleasant scene had been entirely Goode's fault, and a pleasant spirit of mutual cordiality prevailed.
 
Finally Dunmore got up, wiping his mouth on a napkin.
 
"Well, it's about time to get to work," he said. "We might as well save gas and both use my car. Coming, Anton?"
 
"I'm sorry, Fred; I can't leave, yet. I have some notes upstairs I have to get in order. I was working on this new egg-powder, last evening, and I want to continue the experiments at the plant laboratory. I think I know how we'll be able to cut production costs on it, about five per cent."
 
"And boy, can we stand that!" Dunmore grunted. "Well, be seeing you at the plant."
 
Rand waited until Dunmore had left, then went across to the library and up to the gunroom. As soon as he entered the room above, he saw what was wrong. The previous thefts had been masked by substitutions, but whoever had helped himself to one of the more recent metallic-cartridge specimens, the night before, hadn't bothered with any such precaution, and a pair of vacant screwhooks disclosed the removal. A second look told Rand what had been taken: the little .25 Webley & Scott from the Pollard collection, with the silencer.
 
The pistol-trade which had been imposed on him had disquieted him; now, he had no hesitation in admitting to himself, he was badly scared. Whoever had taken that little automatic had had only one thought in mind—noiseless and stealthy murder. Very probably with one Colonel Jefferson Davis Rand in mind as the prospective corpse.
 
He sat down at the desk and started typing, at the same time trying to keep the hall door and the head of the spiral stairway under observation. It was an attempt which was responsible for quite a number of typographical errors. Finally, Anton Varcek came in from the hallway, approached the desk, and sat down in an armchair.
 
"Colonel Rand," he began, in a low voice, "I have been thinking over a remark you made, last evening. Were you serious when you alluded to the possibility that Lane Fleming had been murdered?"
 
"Well, the idea had occurred to me," Rand understated, keeping his right hand close to his left coat lapel. "I take it you have begun to doubt that it was an accident?"
 
"I would doubt a theory that a skilled chemist would accidentally poison himself in his own laboratory," Varcek replied. "I would not, for instance, pour myself a drink from a bottle labeled HNO3 in the belief that it contained vodka. I believe that Lane Fleming should be credited with equal caution about firearms."
 
"Yet you were the first to advance the theory that the shooting had been an accident," Rand pointed out.
 
"I have a strong dislike for firearms." Varcek looked at the pistols on the desk as though they were so many rattlesnakes. "I have always feared an accident, with so many in the house. When I saw him lying dead, with a revolver in his hand, that was my first thought. First thoughts are so often illogical, emotional."
 
"And you didn't consider the possibility of suicide?"
 
"No! Absolutely not!" The Czech was emphatic. "The idea never occurred to me, then or since. Lane Fleming was not the man to do that. He was deeply religious, much interested in church work. And, aside from that, he had no reason to wish to die. His health was excellent; much better than that of many men twenty years his junior. He had no business worries. The company is doing well, we had large Government contracts during the war and no reconversion problems afterward, we now have more orders than we have plant capacity to fill, and Mr. Fleming was consulting with architects about plant expansion. We have been spared any serious labor troubles. And Mr. Fleming's wife was devoted to him, and he to her. He had no family troubles."
 
Rand raised an eyebrow over that last. "No?" he inquired.
 
Varcek flushed. "Please, Colonel Rand, you must not judge by what you have seen since you came here. When Lane Fleming was alive, such scenes as that in the library last evening would have been unthinkable. Now, this family is like a ship without a captain."
 
"And since you do not think that he shot himself, either deliberately or inadvertently, there remains the alternative that he was shot by somebody else, either deliberately or, very improbably, by inadvertence," Rand said. "I think the latter can be safely disregarded. Let's agree that it was murder and go on from there."
 
Varcek nodded. "You are investigating it as such?" he asked.
 
"I am appraising and selling this pistol collection," Rand told him wearily. "I am curious about who killed Fleming, of course; for my own protection I like to know the background of situations in which I am involved. But do you think Humphrey Goode would bring me here to stir up a lot of sleeping dogs that might awake and grab him by the pants-seat? Or did you think that uproar in the library last evening was just a prearranged act?"
 
"I had not thought of Humphrey Goode. It was my understanding that Mrs. Fleming brought you here."
 
"Mrs. Fleming wants her money out of the collection, as soon as possible," Rand said. "To reopen the question of her husband's death and start a murder investigation wouldn't exactly expedite things. I'm just a more or less innocent bystander, who wants to know whether there is going to be any trouble or not.... Now, you came here to tell me what happened on the night of Lane Fleming's death, didn't you?"
 
"Yes. We had finished dinner at about seven," Varcek said. "Lane had been up here for about an hour before dinner, working on his new revolver; he came back here immediately after he was through eating. A little later, when I had finished my coffee, I came upstairs, by the main stairway. The door of this room was open, and Lane was inside, sitting on that old shoemaker's-bench, working on the revolver. He had it apart, and he was cleaning a part of it. The round part, where the loads go; the drum, is it?"
 
"Cylinder. How was he cleaning it?" Rand asked.
 
"He was using a small brush, like a test-tube brush; he was scrubbing out the holes. The chambers. He was using a solvent that smelled something like banana-oil."
 
Rand nodded. He could visualize the progress Fleming had made. If Varcek was telling the truth, and he remembered what Walters had told him, the last flicker of possibility that Lane Fleming's death had been accidental vanished.
 
"I talked with him for some ten minutes or so," Varcek continued, "about some technical problems at the plant. All the while, he kept on working on this revolver, and finished cleaning out the cylinder, and also the barrel. He was beginning to put the revolver together when I left him and went up to my laboratory.
 
"About fifteen minutes later I heard the shot. For a moment, I debated with myself as to what I had heard, and then I decided to come down here. But first I had to take a solution off a Bunsen burner, where I had been heating it, and take the temperature of it, and then wash my hands, because I had been working with poisonous materials. I should say all this took me about five minutes.
 
"When I got down here, the door of this room was closed and locked. That was most unusual, and I became really worried. I pounded on the door, and called out, but I got no answer. Then Fred Dunmore came out of the bathroom attached to his room, with nothing on but a bathrobe. His hair was wet, and he was in his bare feet and making wet tracks on the floor."
 
From there on, Varcek's story tallied closely with what Rand had heard from Gladys and from Walters. Everybody's story tallied, where it could be checked up on.
 
"You think the murderer locked the door behind him, when ............