The Empty Chair (Lincoln Rhyme 3)

Detergent

Camphene

Rhyme gazed at it. More questions than answers....

Fish out of water...

His eye fell on the pile of dirt that Ben had dug out of the boy's shoe. Then something occurred to him. "Jim!" he shouted, his voice booming and startling both Thom and Ben. "Jim! Where the hell is he? Jim!!"

"What?" The sheriff came running into the room, alarmed. "Something wrong?"

"How many people work in the building here?"

"I don't know. 'Bout twenty."

"And they live all over the county?"

"More'n that. Some travel from Pasquotank, Albemarle and Chowan."

"I want 'em all down here now."

"What?"

"Everybody in the building. I want soil samples from their shoes... Wait: And the floor mats in their cars."

"Soil..."

"Soil! Dirt! Mud! You know. I want it now!"

Bell retreated. Rhyme said to Ben, "That rack? Over there?"

The zoologist lumbered toward the table on which was a long rack holding a number of test tubes.

"It's a density gradient tester. It profiles the specific gravity of materials like dirt."

He nodded. "I've heard of it. Never used one."

"It's easy. Those bottles there--" Rhyme was looking toward two dark glass bottles. One labeled tetra, the other ethanol. "You're going to mix those the way I tell you and fill up the tubes close to the top."

"Okay. What's that going to do?"

"Start mixing. I'll tell you when we're through."

Ben mixed the chemicals according to Rhyme's instructions and then filled twenty of the tubes with alternating bands of different colored liquids--the ethanol and the tetrabromoethane.

"Pour a little of the soil sample from Garrett's shoe into the tube on the left. The soil'll separate and that'll give us a profile. We'll get samples from employees here who live in different areas of the county. If any of them match Garrett's that means the dirt he picked up could be from nearby."

Bell arrived with the first of the employees and Rhyme explained what he was going to do. The sheriff grinned'in admiration. "That's an idea and a half, Lincoln. Cousin Roland knew what he was doing when he sang your praises."

But the half hour spent on this exercise was futile. None of the samples submitted from the people in the building matched the dirt in the treads of Garrett's shoe. Rhyme scowled as the last sample of dirt from the employees settled into the tube.

"Damn."

"Was a good try though," Bell said.

A waste of precious time.

"Should I pitch out the samples?" Ben asked.