"Nothing," Cooper said.
"VMD?"
Vacuum metal deposition is the Cadillac of techniques for raising latent prints on nonporous surfaces. It evaporates gold or zinc in a vacuum chamber containing the object to be tested; the metal coats the latent print, making the whorls and peaks very visible.
But Cooper didn't have a VMD with him.
"What do you have?" asked Rhyme, not pleased.
"Sudan black, stabilized physical developer, iodine, amido black, DFO and gentian violet, Magna-Brush."
He'd also brought ninhydrin for raising prints on porous surfaces and a Super Glue frame for smooth surfaces. Rhyme recalled the stunning news that had swept the forensic community some years ago: A technician working in a U.S. Army forensic lab in Japan had used Super Glue to fix a broken camera and found to his amazement that the fumes from the adhesive raised latent fingerprints better than most chemicals made for that purpose.
This was the method Cooper now used. With forceps he set the rock in a small glass box and put a dab of glue on the hot plate inside. A few minutes later he lifted the rock out.
"We've got something," he said. He dusted it with long-wavelength UV powder and hit it with the beam from the PoliLight wand. A print was clearly visible. Dead center. Cooper photographed it with Polaroid CU-5, a 1:1 camera. He showed the picture to Rhyme.
"Hold it closer." Rhyme squinted as he examined it. "Yes! He rolled it."
Rolling prints--rocking a finger onto a surface--produced an impression different from one made by picking up an object. It was a subtle difference--in the width of the friction ridges at various points on the pattern--but one that Rhyme now recognized clearly.
"And look, what's that?" he mused. "That line." There was a faint crescent mark above the print itself.
"It looks almost like--"
"Yep," Rhyme said, "her fingernail. You wouldn't normally get that. But I'll bet he tipped the stone just to make sure it got picked up. It left an oil impression. Like a friction ridge."
"Why would he do that?" Sachs asked.
Once more miffed that nobody seemed to be picking up these points as fast as he was, Rhyme explained tersely, "He's telling us two things. First, he's making sure we know the victim's a woman. In case we didn't make the connection between her and the body this morning."
"Why do that?" Banks asked.
"To up the ante," Rhyme said. "Make us sweat more. He's let us know there's a woman at risk. He's valuated the victims--just like we all do--even though we claim we don't." Rhyme happened to glance at Sachs's hands. He was surprised to see that, for such a beautiful woman, her fingers were a mess. Four ended in fleshy Band-Aids and several others were chewed to the quick. The cuticle of one was caked with brown blood. He noticed too the red inflammation of the skin beneath her eyebrows, from plucking them, he assumed. And a scratch mark beside her ear. All self-destructive habits. There're a million ways to do yourself in besides pills and Armagnac.
Rhyme announced, "The other thing he's telling us I already warned you about. He knows evidence. He's saying, Don't bother with regular forensic PE. I won't be leaving any. That's what he thinks of course. But we'll find something. You bet we will." Suddenly Rhyme frowned. "The map! We need the map. Thom!"
The aide blurted, "What map?"
"You know what map I mean."
Thom sighed. "Not a clue, Lincoln."
Glancing out the window and speaking half to himself, Rhyme mused, "The railroad underpass, the bootleg tunnels and access doors, the asbestos--those're all old. He likes historical New York. I want the Randel map."
"Which is where?"
"The res
earch files for my book. Where else?"
Thom dug through folders and pulled out a photocopy of a long, horizontal map of Manhattan. "This?"
"That, yes!"
It was the Randel Survey, drawn in 1811 for the commissioners of the city to plan out the grid of streets in Manhattan. The map had been printed horizontally, with Battery Park, south, to the left and Harlem, north, to the right. Laid out this way, the island resembled the body of a dog leaping, its narrow head lifted for an attack.
"Pin it up there. Good."