“I did not,” said Bell. “But I did ask the engineers to explain what happened. They refer to that section of the tunnel between Thirty-fourth Street and Grand Central Terminal as the hoodoo part. All sorts of terrible things have gone wrong with its construction—a deadly explosion of blasting powder, rockfalls, a contractor killed. What happened today was the result of an unforeseen geological fault. The man I was chasing precipitated the slide—either by accident as he tried to escape or deliberately if he had knowledge of mine engineering and recognized the flaw in the rock.”

Van Dorn spoke in a voice that rose. “Rest assured, I do not believe that any of my detectives would deliberately precipitate the collapse of a city block, but I would hope that at future such events you would not stick around to allow the police to link the name of the Van Dorn Agency to a natural disaster.”

“I had to help some people out of the buildings.”

“You’re sure you’d seen this man before?”

“I’m not sure,” Bell said, because he was not yet able to explain, to the Boss’s satisfaction, his strange, dreamlike memory of the man with amber eyes who had to be the provocateur. “But I am convinced that he was looking for me. He lured me into that cellar.”

“Lured?” echoed Van Dorn. “Lured is what penny-dreadful villains do to unsuspecting maidens.”

“What I mean to say is, I feel like a darn fool.”

Van Dorn nodded agreement. “I think you could do with a night’s rest.”

“Yes, sir,” said Isaac Bell. But instead of going home to his room in the Yale Club, he went straight to a gunsmith that Wish Clarke patronized on Forty-third Street. It was after hours, but the gunsmith lived above his shop, and Wish’s name got Bell in the door.

He bought a two-shot derringer, a tiny one-shot, and a Colt Army to replace the weapons taken by the amber-eyed man. Then he described the man’s revolver to the smith.

“It was a .45. And I would have thought it was a Colt. But it had no front sight. And the hammer was much wider than this,” he added, hefting the gun. “I was wondering, do you know a smith who might modify a Colt that way?”

“Folks do all sorts of things to six-shooters. Did you notice the top strap?”

“It was flat,” said Bell. “Not beveled like this. And the hammer had a graceful little curl to it.”

“Was the front sight cut off or ground down?”

Bell considered for a moment. “No. There seemed to be a notch you could slip one into.”

“How long was the barrel?”

“Not so long it couldn’t come out of his holster real quick.”

“And it had a slot for the front sight? . . . Did you get a look at the trigger?”

“No. His finger was curled around it.”

“How big was the grip?”