Steele said, “That’s odd. I hadn’t noticed that before. I was down here with the police, too. It’s just a little smear.”
Mason said, “The paint’s dry now. You say it dries in six hours?”
“Yes, four to six hours. That’s what Mr. Gentrie told me. Of course, that’s the only way I have of knowing.”
“Let’s look for that tin,” Rebecca said, moving along the workbench, sniffing and peering at the assortment of tools. “Here’s a can with paint brushes in it. Could this be it, Delman?”
“That’s it,” Delman said. “You can always tell the way Mr. Gentrie opens a can. He never runs the opener all the way around. He stops just before he cuts the lid entirely free. He always leaves a strip of tin of about a sixteenth of an inch, then twists the lid off.”
“That’s right,” Mrs. Gentrie confirmed. “He says that if you go farther than that, the top of the can falls down on the inside. I always hold up the lid and then finish cutting. Arthur twists. You can see where the top of this can was twisted off.”
Mason thoughtfully regarded the tin. “Let’s take a look at the top of the can just to make our investigation complete,” he said.
“At the top of the can!” Mrs. Gentrie asked.
Mason nodded.
“Well, probably we can find it if we look through this box of scraps, but, for the life of me, I can’t see what...”
Steele said, “I noticed it lying here on the bench last night. There it is, over there near the corner. He used it to set a paint can on.”
Mason picked up the circular tin top and examined the distinctive place where it had been twisted off.
“This the one?” he asked.
“That’s it,” Steele said. “I remember that little distinctive twist on the tin. You can see where it was turned...”
Mason’s eyes showed keen interest. “Wait a minute,” he said. “This isn’t right.”
“What’s wrong with it?”
Mason said, “The lid that was on the tin was twisted off to the left. This one is twisted off to the right.”
Steele bent forward and regarded the circular piece of tin, then went over to look at the can. “Well, I’ll be darned,” he said. “I saw that piece of tin lying here on the counter last night and naturally supposed it had come off this can. Why in the world would Mr. Gentrie have opened the can, thrown the top away, then taken the top from another tin out of that box of scraps? But Gentrie is left-handed. You’re right about that top — but, why...?”
“I don’t know why,” Mason said, “but that’s very evidently what he did. Let’s take a look over here in this box of scraps.”
Rebecca said tartly to Mrs. Gentrie, “I told you it had something to do with what happened over there. You can see what happens when a trained mind starts working on the problem.”
Mrs. Gentrie sighed. “I’m afraid I’d make a poor detective,” she said. “It certainly seemed trivial enough.”
Mason smiled. “I’m afraid I’m like your sister-in-law Mrs. Gentrie. Whenever there’s anything the least bit out of the ordinary, I start making a mystery out of it. After all, you know, it is rather a peculiar place for an empty tin, and I can’t imagine why anyone would seal up an entirely empty tin. There must have been something in it.”
“Well, I shook it and didn’t hear anything. And goodness knows the can was light enough to be empty. It couldn’t have had anything in it. Of course, now that I see everyone making so much of a point of it, it...”
“And unless I’m mistaken,” Mason, who had been leaning over the scrap box, interposed, “this is the top which came off the can.” He reached down into the tangled mass of tin.
“Watch out you don’t cut your hand in there,” Mrs. Gentrie warned sharply.
Junior laughed and said, “Mr. Mason doesn’t need to be a detective to tell you’re the mother of three children, Ma. ‘Don’t do this, and don’t do that.’ ”
Mason straightened up with a piece of tin in his hand, walked over to the can in which the paint brushes were deposited, and held the circular piece of tin over the top so that the little twisted nipple of tin which had been left on the can was placed against the corresponding point on the circular piece.
“That’s it all right,” Steele said.
Junior reached out eagerly. “Gee, Mr. Mason, let me take a...”
“Junior,” Mrs. Gentrie rebuked, “don’t interfere with what Mr. Mason is doing.”
Mason said, “The underside seems to be all scratched up. It feels rough to the touch. Let’s just examine those scratches. We’ll tilt it over here near the window so that the light comes across it from the side, and...”
“It’s a code,” Rebecca shrilled excitedly. “Something written on there... scratched on the tin! I knew it! I just knew it! I told you so, Florence. You wouldn’t listen to me, but...”
Mason whipped a pencil from his pocket and tore a sheet of paper from his notebook. “Will someone write these letters as I read them off?” he asked.
Rebecca said eagerly, “I will.”
Mason handed her the paper and pencil, tilting the lid, so that he could get a side lighting on the letters as he read.
“CKDACK CJIAJ DLACC HEDBCE CEIADD GIKADC CLDGBD KFBCH CLGGBJ.”
Mason took the piece of paper from Rebecca and carefully checked the letters she had written with the original.
“I don’t see how this could have had anything to do with what happened across the street,” Mrs. Gentrie said, frankly puzzled.
Mason slipped the sharp-edged circle of tin into the side pocket of his coat. “It may be just a coincidence,” he agreed. “Rather peculiar, that’s all. How many of you heard the shot?”
“I did,” Mrs. Gentrie said.
Steele said, “I was sleeping soundly, and was wakened by the noise. I suppose it was all over when I woke up, but I tried to reconstruct what had wakened me, and somehow had the impression there were two shots.”
“Did you mention that to Lieutenant Tragg — the head of the Homicide Squad?” Mason asked.
“I don’t think I did,” Steele said. “He seemed quite positive there was only one shot, and I didn’t contradict him. Of course, my impressions were very vague, just trying to recall a noise which has wakened you from a sound sleep. It’s just a vague feeling, anyhow — an echo in the back of the consciousness, if you know what I mean.”
Mason said, “I know exactly what you mean, and you express it very well indeed. It might be a good plan for you to get in touch with Lieutenant Tragg and tell him that, after thinking it over, you believe it’s very possible there were two shots.”
“There weren’t,” Rebecca said positively. “Only one. I was wide awake at the time. I thought it might have been a backfire from an automobile or truck. I know there was only one shot.”
Mason turned to Junior, raised his eyebrows.
Junior shook his head. “I can’t help you at all. I slept right through the whole commotion. I couldn’t have been in bed very long when it happened either, probably not more than fifteen or twenty minutes.”
“What time was the shot?”
“Around twelve-thirty, I believe.”
“What time did you get to bed?”
“Ten or fifteen minutes after midnight. I just shed my clothes all over the room and dove into bed. I’d been out with a young lady, and had taken her home. I thought I was going to have to work today, and — well, I just can’t seem to get enough sleep.”
Mrs. Gentrie said solicitously, “Junior, don’t you think you should tell Mr. Mason with whom you spent the evening?”
Junior colored. “No,” he said shortly.