The Empty Chair

Lucy glanced at the real estate overlooking the canal – the elegant new colonials Sachs had seen earlier – and said nothing.

Again Sachs was struck by the forlorn quality of the houses and yards, the absence of kids. Just like the streets of Ta

Children, she reflected again.

Then told herself: Let's not get into that.

Lucy turned right on Route 112 then off onto the shoulder – where they'd been just a half hour earlier, the ridge overlooking the crime scenes. Jesse Corn's squad car pulled in behind. The four of them walked down the embankment to the riverside and climbed into the skiff. Jesse took up the rowing position again, muttered, "Brother, north of the Paquo." He said this with an ominous tone that Sachs at first took to be a joke but then noticed that neither he nor the others were smiling. On the far side of the river they climbed out and followed Garrett's and Lydia 's footsteps to the hunting blind where Ed Schaeffer had been stung then about fifty feet past it into the woods, where the tracks vanished.

At Sachs' direction they fa

Lucy said to Jesse, "You know that path? The one those druggies scooted down after Frank Sturgis found 'em over last year?"

He nodded. He said to Sachs, "It's about fifty yards north. That way." He pointed. "Garrett'd know about it probably and it's the best way to get through the woods and swamp here."

"Let's check it out," Ned said.

Sachs wondered how to best handle the impending conflict and decided there was only one way: head-on. Being overly delicate wouldn't work, not with three of them versus her alone (Jesse Corn being, she believed, only amorously in her camp). "We should stay here until we hear from Rhyme."

Jesse kept a faint smile on his face, tasting a morsel of divided loyalty.

Lucy shook her head. "Garrett had to've taken that path."

"We don't know that for sure," Sachs said.

"It does get a little thick 'round here," Jesse offered.

Ned said, "All that plume grass and tuckahoe and mountain holly. Lot of creeper too. You don't take that path, there's no way to get through here and make any time."

"We'll have to wait," Sachs said, thinking of a passage from Lincoln Rhyme's textbook on criminalistics, Physical Evidence:

More investigations involving a suspect at large are ruined by giving in to the impulse to move quickly and engage in hot pursuit when, in fact, in most cases, a slow examination of the evidence will point a clear path to the suspect's door and permit a safer and more efficient arrest.

Lucy Kerr said, "It's just that somebody from the city doesn't really understand the woods. You head off that path it'd slow your time by half. He had to've stuck to it."

"He could've doubled back to the riverbank," Sachs pointed out. "Maybe he had another boat hidden up – or downstream."

"That's true," Jesse said, earning a dark glance from Lucy.

A long moment of silence, the four people standing immobile while gnats strafed them and they sweated in the merciless heat.

Finally Sachs said simply, "We'll wait."

Sealing the decision, she sat on what was surely the most uncomfortable rock in the entire woods and, with feigned interest, studied a woodpecker drilling fiercely into a tall oak in front of them.

9

"Primary scene first," Rhyme called to Ben. "Blackwater."

He nodded at the cluster of evidence on the fiberboard table. "Let's do Garrett's ru

Ben picked it up, unzipped the plastic bag, started to reach inside.

"Gloves!" Rhyme ordered. "Always wear latex gloves when handling evidence."

"Because of fingerprints?" the zoologist asked, hurriedly pulling them on.

"That's one reason. The other's contamination. We don't want to confuse places you've been with places the perp has been."

"Sure. Right." Ben nodded his massive crew-cut head aggressively, as if he were fearful of forgetting this rule.

He shook the shoe, peered into it. "Looks like there's gravel or something inside."

"Hell, I didn't have Amelia ask for sterile examining boards." Rhyme looked around the room. "See that magazine there? People?"

Ben picked it up. Shook his head. "It's three weeks old."

"I don't care how current the stories about Leonardo DiCaprio's love life are," Rhyme muttered. "Pull out the subscription inserts inside… Don't you hate those things? But they're good for us – they come off the printing press nice and sterile, so they make good mini-examining boards."

Ben did as instructed and poured the dirt and stones onto the card.

"Put a sample in the microscope and let me take a look at it." Rhyme wheeled close to the table but the ocular piece was a few inches too high for him. "Damn."

Ben assessed the problem. "Maybe I could hold it for you to look in."

Rhyme gave a faint laugh. "It weighs close to thirty pounds. No, we'll have to find a – "

But the zoologist picked up the instrument and, with his massive arms, held the 'scope very steady. Rhyme couldn't, of course, turn the focusing knobs but he saw enough to give him an idea of what the evidence was. "Limestone chips and dust. Would that've come from Blackwater Landing?"

"Uhm," Ben said slowly, "doubt it. Mostly just mud and stuff."

"Run a sample of it through the chromatograph. I want to see what else is in there."

Ben mounted the sample inside and pressed the test button.

Chromatography is a criminalist's dream tool. Developed just after the turn of the century by a Russian botanist though not much used until the 1930s, the device analyzes compounds such as foods, drugs, blood and trace elements and isolates the pure elements in them. There are a half-dozen variations on the process but the most common type used in forensic science is the gas chromatograph, which burns a sample of evidence. The resulting vapors are then separated to indicate the component substances that make up the sample. In a forensic science lab the chromatograph is usually co

The gas chromatograph will only work with materials that can be vaporized – burned – at relatively low temperatures. The limestone wouldn't ignite, of course. But Rhyme wasn't interested in the rock; he was interested in what trace materials had adhered to the dirt and gravel. This would narrow down more specifically the places Garrett had been.

"It'll take a little while," Rhyme said. "While we're waiting let's look at the dirt in the treads of Garrett's shoe. I tell you, Ben, I love treads. Shoes, and tires too. They're like sponges. Remember that."

"Yessir. I will, sir."

"Dig some out and let's see if it comes from someplace different from Blackwater Landing."

Ben scraped the dirt onto another subscription card, which he held in front of Rhyme, who examined it carefully. As a forensic scientist, he knew the importance of dirt. It sticks to clothes, it leaves trails like Hansel's and Gretel's bread crumbs to and from a perp's house and it links criminal and crime scene as if they were shackled together. There are approximately 1,100 different shades of soil and if a sample from a crime scene is the identical color to the dirt in the perp's backyard the odds are good that the perp was there. Similarity in the composition of the soils can bolster the co