"What's the idea?" Drake asked.

Mason said, "If we fire a bullet through that gun now, there will be striations that are in addition to and different from those of the test bullets that have previously been fired through it. Is that right?"

"If you want to be sure, better make a couple of more marks," Drake said.

Mason repeated the process of scratching the barrel. "How's that?"

"That should do it very nicely," Drake said.

Mason opened the drawer of his desk and dropped the gun down in the drawer.

Drake regarded him thoughtfully. "You know, there's a law about tampering with evidence."

"Evidence of what?" Mason asked.

"I don't know," Drake said.

Mason grinned. "We're not supposed to be clairvoyant, Paul. If you adopt that attitude, you could never change anything in connection with any object. You couldn't even tear up a piece of paper and throw it away. You couldn't wash a dirty dish. You'd be altering or destroying evidence. Any object doesn't become evidence until you know or have reason to believe that it has become identified with a crime in some manner."

"And you have no reason to believe that this gun is connected with a crime?"

"Very definitely not," Mason said. "I am simply protecting a client."

"And that will protect the client?" Drake asked.

"It may help," Mason said. "I'm sitting in a game where I don't know what cards have been played and moreover I don't know what are trumps. But we've been dealt a hand. It may not be a very good hand. It probably was dealt to us from a cold deck with the idea that it was the lowest hand in the deck. I've got to play that hand so it becomes a winning hand."

"Without knowing trumps and without knowing what cards have already been played?"

"That's right."

"That's a job you can have," Drake said. "I'm glad I'm not a lawyer. Anything else before I go home, Perry?"

"Not right now."

Drake got to his feet, moved lazily toward the door, paused at the entrance door to look back at Mason. "This deal in Rowena could be bad business," he said. "There's a lot of money involved."

"That's right," Mason said.

Drake hesitated a moment longer, then shrugged his shoulders, opened the door and walked out.

Della Street looked at Mason and raised her eyebrows in silent inquiry.

"Now then," Mason said, "we know this gun is the property of George Anclitas. I want to get it back to his place of business. We have to-"

The lawyer was interrupted by the ringing of the telephone.

"That's Gertie," Mason said. "See what it is, Della."

Della Street picked up the telephone, said, "Yes, Gertie," then said, "Just a minute." She looked at Mason. "Mr. Helman Ellis is in the outer office and says it is very important that he get in touch with you at the earliest possible moment. He realizes it's after office hours but he wants to know if you can see him immediately."

Mason hesitated a moment, appraising the situation, then said, "I'll see him immediately, Della. Go out and bring him in."

Della Street said, "I'll be right out, Gertie," and hung up the phone.

"Go through the usual routine," Mason instructed her. "Get his name, address, telephone number where he can be reached, and then bring him in."

Della nodded, then walked out through the doorway to the reception room.

A few minutes later she returned and said, "Mr. Mason, Mr. Ellis."

Mason got up to shake hands.

Ellis was a tall individual in his late twenties. He had high cheekbones, a somewhat Slavic cast of features, a long, thin mouth, steady blue eyes. He was big-boned and wrapped powerful fingers around Mason's hand as the two men shook hands.

"Sit down," Mason said. "Is there anything I can do for you?"

"I don't know," Ellis said. "It depends on how you're tied up."

"I am representing Ellen Robb."

"That's why I'm here," Ellis said.

"What is your trouble?"

"My wife."

"I don't take divorce cases," Mason said. "I try to specialize pretty much in trial work. A good deal of my practice is criminal cases. Domestic relations, contracts and all that just don't appeal to me."

"My wife," Ellis said simply, "is going to kill your client."

Mason raised his eyebrows.

"There is no real cause for jealousy," Ellis said, "but my wife has in my opinion become temporarily insane."

Mason said, "Let's get certain facts straight. You have been playing a lot of poker at The Big Barn and you've lost rather heavily?"

"That's right."

"Your wife didn't take kindly to the idea?"

"Wives don't take kindly to the idea of husbands sitting in poker games and losing money."

"And Ellen Robb was rather conspicuous around The Big Barn?"

"They made her conspicuous," Ellis said.

"And you became interested in her?"

Ellis took a deep breath and said, "Mr. Mason, I love her."

"And yet you say your wife has no reason to be jealous?"

"I'll put it this way, Mr. Mason. I hadn't-I have been keeping it to myself."

"You mean you think you've been keeping it to yourself," Mason said.

"What do you mean by that?"

"A wife can smell a situation of that sort a mile away," Mason said. "If you're in love with Ellen Robb, you can rest assured that your wife knew there was something more to your excursions to The Big Barn than a desire to sit in a poker game."

"She doesn't know how I really feel," Ellis said, "because it was only recently I faced the situation myself and realized I had fallen in love."

"She knew it before you did," Mason said, "otherwise, why should she have become so jealous?"

"She's always been jealous. She's jealous of any woman that I look at twice."

"Have you looked at many women twice?"

"Not much more than that."

"All right. Tell me what happened."

"Well, I knew that Nadine, my wife, was building up to terrific emotional tension. I'd lost some money playing poker but I could afford to lose money playing poker. Then she made a scene. You know all about that-that was one thing I couldn't afford, to be branded as a welsher.

"Mr. Mason, if Nadine had filed suit against George Anclitas on account of money that I lost playing poker, I would be branded from coast to coast as a piker, a welsher."

"Suppose the game was crooked?"

"That, of course, is different. If anyone could prove the game was crooked, the situation would be different."

"All right. What happened?" Mason asked. "Let's get down to brass tacks."

"I learned that my wife had made a scene down at The Big Barn. I learned that you had given her some legal authorities which would enable her to try to recover the money I had lost. I learned that she had gone to an attorney and retained him to file suit. So I told Nadine that we simply had to talk things out. We decided to go on a cruise on my yacht. We would be uninterrupted that way. We could sail out beyond the harbor and try to get the whole thing settled. We'd done that once or twice before during periods of crisis in our married life, and things had worked out all right."

"How long have you been married?" Mason asked.

"Seven years."

"All right, go on. What happened?"

"We left the house," Ellis said, "to go to the yacht. We told the neighbors that we would probably be out all night or perhaps two nights. We planned to sleep on the yacht. We planned to have dinner on the yacht. We stopped to buy some provisions.

"It seems that almost immediately after we left the house, Ellen showed up. She wanted to talk to my wife. The neighbor told her we were down on the yacht so Ellen went down there, rented a skiff and rowed out to where the yacht was moored. She rowed all around it and called out several times. Then she tied up the skiff and went aboard. When she didn't find anyone there, she took the skiff and rowed back to the place where she had rented the skiff.