The tech lifted them off with a pair of tweezers and mounted them on slides. He put them under the stereo binocular microscope--the preferred instrument for analyzing fibers--and then hit a button. The image he was looking at through the eyepiece popped onto the large flat-screen computer monitor for everyone to see.
The fibers appeared as thick strands, grayish in color.
Fibers are important forensic clues because they're common, they virtually leap from one source to another and they can be easily classified. They fall into two categories: natural and man-made. Rhyme noted immediately that these weren't viscous rayon or polymer based and therefore had to be natural.
"But what kind specifically?" Mel Cooper wondered aloud.
"Look at the cell structure. I'm betting it's excremental."
"Whatsat?" Sellitto asked. "Excrement? Like shit?"
"Excrement, like silk. It comes from the digestive tract of worms. Dyed gray. Processed to a matte finish. What's on the other slides, Mel?"
He ran these through the scope too and found they were identical fibers.
"Was the perp wearing gray?"
"No," Sellitto reported.
"The vic wasn't either," Sachs said.
More mysteries.
"Ah," Cooper said, peering into the eyepiece, "might have a hair here."
On the screen a long strand of brown hair came into focus.
"Human hair," Rhyme called out, noting hundreds of scales. An animal hair would have at most dozens. "But it's fake."
"Fake?" Sellitto asked.
"Well," he said impatiently, "it's real hair but it's from a wig. Obviously. Look--at the end. That's not a bulb. It's glue. Might not be his, of course, but it's worth putting on the chart."
"That he's not brown-haired?" Thom asked.
"The facts," Rhyme said tersely, "are all we care about. Write that the unsub is possibly wearing a brown wig."
"Okay, bwana."
Cooper continued his examination and found that two of the adhesive squares revealed a minuscule bit of dirt and some plant material.
"Scope the plant first, Mel."
In analyzing crime scenes in New York, Lincoln Rhyme had always placed great importance on geologic, plant and animal evidence because only one-eighth of the city is actually on the North American mainland; the rest is situated on islands. This means that minerals, flora and fauna tend to be more or less common to particular boroughs and even neighborhoods within them, making it easier to trace substances to specific locations.
A moment later a rather artistic image of a reddish twig and a bit of leaf appeared on the screen.
"Good," Rhyme announced.
"What's good about it?" Thom asked.
"It's good because it's rare. It's a red pignut hickory. You hardly ever find them in the city. The only place I know of are Central and Riverside Parks. And . . . oh, look at that. That little blue-green mass?"
"Where?" Sachs asked.
"Can't you see it? It's right there!" Feeling painfully frustrated that he couldn't leap from his chair and tap the screen. "Lower right-hand corner. If the twig's Italy then the mass is Sicily."
"Got it."