"No, you've built up a case. But there's a stronger case already built for us, isn't there? Dingwell exposed the gamblers Blair and Smith, knocked one of them cold, made them dig up a lot of money, and drove them out of town. They left, swearing vengeance. He rides away, and he is never seen again. The natural assumption is that they lay in wait for him and killed him."
"Then where is the body?"
"Lying out in the cactus somewhere—or buried in the sand."
"That wouldn't be a bad guess—if it wasn't for another bit of testimony that came in to show that Dave was alive five hours after he left the Legal Tender. A sheepherder on the Creosote Flats heard the sound of horses' hoofs early next morning. He looked out of his tent and saw three horses. Two of the riders carried rifles. The third rode between them. He didn't carry any gun. They were a couple of hundred yards away and the herder didn't recognize any of the men. But it looked to him like the man without the gun was a prisoner."
"Well, what does that prove?"
"If the man in the middle was Dave—and that's the hunch I'm betting on to the limit—it lets out the tinhorns. Their play would be to kill and make a quick getaway. There wouldn't be any object in their taking a prisoner away off to the Flats. If this man was Dave, Blair and Smith are eliminated from the list of suspects. That leaves the Rutherfords."
"But you don't know that this was Dingwell."
"That's where you come in, me brave Sherlock. Dave's friends can't move to help him. You see, they're all known men. It might be the end of Dave if they lifted a finger. But you're not known to the Rutherfords. You slip in over Wagon Wheel Gap to Huerfano Park, pick up what you can, and come out to Battle Butte with your news."
"You mean—spy on them?"
"Of coorse."