Parking in the drive, Rand entered the Fleming house by the front door. The butler must have been busy with his pre-dinner tasks in the rear; it was Gladys herself who admitted him.  
"Stay out of there," she warned him, taking his arm and guiding him away from the parlor doorway. "Nelda and Geraldine are in there, ignoring each other. If you go in, they'll start talking to you, and then they'll start talking at each other through you, and the air will be full of tomahawks in a jiffy. Let's go up in the gunroom; that's out of the battle zone."
 
"What started the hostilities this time?" Rand asked, going up the stairway with her.
 
"Oh, Geraldine lost Nelda's place-marker out of the Kinsey Report, or something." She shrugged. "Mainly reaction to Rivers's death. That was a great blow to all of us; twenty-five thousand dollars' worth of blow. It was a blow to me, too, but I'm not letting it throw me.... What were you doing all afternoon?"
 
"Trying to keep the rest of our prospects out of jail. This sixteenth-witted District Attorney you have in this county had the idea he could charge Stephen Gresham with the killing. I had a time talking him out of it, and I'm still not sure how far I succeeded. And I was trying to get a line on where those pistols got to."
 
"Ssssh!" They reached the top of the stairs, and Rand saw Walters approaching down the hall. "It was Colonel Rand, Walters; I let him in myself. Are Mr. Varcek and Mr. Dunmore here, yet?"
 
"Mr. Dunmore is in the library, ma'am, and Mr. Varcek is upstairs, in his laboratory. Dinner will be ready in three-quarters of an hour."
 
"Have you mixed the cocktails? You'd better do that. Serve them in about twenty minutes. And you'd better go up and warn Mr. Varcek not to become involved in anything messy before dinner."
 
Walters yes-ma'am'd her and started toward the attic stairway. Rand and Gladys went into the gunroom; Rand turned to the left, picked a pistol from the wall, and carried it with him as he guided Gladys toward the desk in the corner.
 
"You think Walters stole them?" she asked.
 
"So far, I'm inclined to. Have you told any of the others, yet?"
 
"Oh, Lord, no! They'd all be sure that I stole them myself. I'm counting on you to get them back with as little fuss as possible. Do you think that was why Rivers was killed? After all, when a lot of valuable pistols disappear, and a crooked dealer is murdered, I'd expect there to be a connection."
 
"There could be. Did you ever hear any stories about Mrs. Rivers and this young fellow Gillis who works in Rivers's shop?"
 
Gladys laughed. "Is that rearing its ugly head in public, now?" she asked. "Well, there's nothing like a good murder to shake the skeletons out of the closets. Not that this particular skeleton was ever exactly hidden. The stories are numerous, and somewhat repetitious; Cecil and Mrs. Rivers would be seen together, at roadhouses and so on, at what they imagined was a safe distance from Rosemont, and it was said that when Rivers was away over night, Cecil was never seen to leave the Rivers place in the evenings. Might this be relevant to Rivers's sudden demise?"
 
"It could be." Rand was keeping one eye on the hall door and the other on the head of the spiral stairway. "Don't mention outside what I told you about Farnsworth having this brainstorm about Stephen Gresham. If it got out, it might hurt Gresham professionally. The fact is, Gresham has just retained me to investigate the Rivers murder for him. That won't interfere to any great extent with the work I'm doing here; if necessary, I'll bring a couple of my men in from New Belfast to help me on the Rivers operation." He broke off abruptly, catching a movement at the head of the spiral, and lifted the pistol in his hand, as though showing it to Gladys. "See," he went on, "it has two hammers and two nipples, but only one barrel. It was loaded with two charges, one on top of the other; the bullet of the rear charge acted as the breech-plug for the front charge.... Oh, Walters!" He affected to catch sight of the butler for the first time. "Bring me that .36 Walch revolver, will you?"
 
"Yes, sir." Walters, crossing the room, veered to the right and went to the middle wall, bringing a revolver over to the desk. It was a percussion weapon with an abnormally long cylinder. "The cocktails are served," he announced.
 
"We'll be down in a moment; you can put these back where they belong when you find time," Rand told him. "Now, here," he said to Gladys. "This is the same idea, in a revolver. Six chambers, two charges in each. In theory, it was a good idea, but in actual practice ..."
 
Walters went out the hall door, presumably to call Varcek. Rand continued talking about the superposed-load principle, as used in the Lindsay pistol and the Walch revolver, until he was sure the butler was out of hearing. Gladys was looking at him in appreciative if slightly punch-drunk delight.
 
"I wondered why you brought that thing over here with you," she said. "Brother, was that a quick shift!... You're really sure he's the one?"
 
"I'm not really sure of anything, except of my own existence and eventual extinction," Rand told her. "It pretty nearly has to be somebody inside this house. I don't think anybody else here, yourself included, would know enough about arms to rob this collection as selectively as it has been robbed. Did you see what just happened, here? I asked him for one of the most uncommon arms here, and he went straight and got it. He knows this collection as well as your husband did, and I assume he knows values almost as well.... And, of course, there was a musket, too; Mr. Fleming didn't collect long-arms, or he'd have had one. It embodied the same principle as the pistol. The legend is that this man Lindsay's brother was a soldier; he was supposed to have been killed by Indians who drew the fire of the detail he was with and then charged them when their muskets were empty." Rand shrugged. "Actually, the superposed-load principle is ancient; there's a sixteenth-century wheel lock pistol in the Metropolitan Museum, in New York, firing two shots from the same barrel."
 
Varcek and the butler, who had entered by the hall door, went across the gunroom and down the spiral. Rand laid down the pistol and escorted Gladys after them.
 
Dunmore and Geraldine were in the library when they went down. Geraldine, mildly potted, was reclining in a chair, sipping her drink. Dunmore was still radiating his synthetic cheerfulness.
 
"Get many of the pistols listed, Colonel?" he hailed Rand, with jovial condescension.
 
"No." Rand poured two cocktails, handing one to Gladys. "I went to Arnold Rivers's place this morning, on a little unfinished business, and damn near tripped over Rivers's corpse. I spent the rest of the day getting myself disinvolved from the ensuing uproar," he told Dunmore. "You heard about it, of course."
 
"Yes, of course. Horrible business. I hope you didn't get mixed up in it any more than you had to. After all, you're working for us, and if the police knew that, we'd be bothered, too.... Look here, you don't think some of these other people who were after the collection might have killed Rivers, to keep him from outbidding them?"
 
Nelda, entering from the hallway, caught the last part of that.
 
"Good God, Fred!" she shrieked at him. "Don't say things like that! Maybe they did, but wait till they've bought the collection and paid for it, before you start accusing them!"
 
"I'm not accusing anybody," Dunmore growled back at her. "I don't know enough about it to make any accusations. All I'm saying is—"
 
"Well, don't say it, then, if you don't know what you're talking about," his wife retorted.
 
In spite of this start, dinner passed in relative quiet. For the most part, they talked about the remaining chances of selling the collection, about which nobody was optimistic. Rand tried to build up morale with pictures of large museums and important dealers, all fairly slavering to get their fangs into the Fleming collection, but to little avail. A pall of gloom had settled, and he was forced to concede that he had at last found somebody who had a valid reason to mourn the sudden and violent end of Arnold Rivers.
 
Dinner finished, he went up to the gunroom and began compiling his list. He found a yardstick, and thumbtacked it to the edge of the desk to get over-all and barrel lengths, and used a pair of inside calipers and a decimal-inch rule from the workbench to get calibers. Sticking a she............