The Empty Chair by Jeffery Deaver Page A

at the crime scene.
    The first step in dirt analysis is to check known soil from the scene – an exemplar – against the sample the criminalist believes came from the perp.
    Rhyme explained this to Ben and the big man picked up one bag of dirt, which Sachs had marked Exemplar soil – Blackwater Landing , along with the date and time of collection. There was also a notation in a hand that was not Sachs'. Collected by Deputy J. Corn. Rhyme pictured the young deputy eagerly scurrying off to do her bidding. Ben poured some of this dirt onto a third subscription card. He set it beside the dirt he'd dug out of Garrett's treads. "How do we compare them?" the young man asked, looking over the instruments.
    "Your eyes."
    "But – "
    "Just look at them. See if the color of the unknown sample is different from the color of the known."
    "How do I do that?"
    Rhyme forced himself to answer calmly. "You just look at them."
    Ben stared at one pile, then the other.
    Back again. Once more.
    And then once again.
    Come on, come on . . . it isn't that tricky. Rhyme struggled to be patient. One of the hardest things in the world for him.
    "What do you see?" Rhyme asked. "Is the dirt from the two scenes different?"
    "Well, I can't exactly tell, sir. I think one's lighter."
    "'Scope them in the comparison."
    Ben mounted the samples in a comparison microscope and looked through the eyepieces. "I'm not sure. Hard to say. I guess . . . maybe there is some difference."
    "Let me see."
    Once again the massive muscles held the large microscope steady and Rhyme peered into the eyepieces. "Definitely different from the known," Rhyme said. "Lighter-colored. And it has more crystal in it. More granite and clay and different types of vegetation. So it's not from Blackwater Landing . . . If we're lucky it came from his hidey-hole."
    A faint smile crossed Ben's lips, the first Rhyme had seen.
    "What?"
    "Oh, well, that's what we call the cave a moray eel takes for his home . . ." The young man's smile vanished as Rhyme's stare told him that this was not the time or place for anecdotes.
    The criminalist said, "When you get the results of the limestone on the chromatograph run the dirt from the treads."
    "Yessir."
    A moment later the screen of the computer attached to the chromatograph/spectrometer flickered and lines shaped like mountains and valleys appeared. Then a window popped up and the criminalist maneuvered closer in his wheelchair. He bumped a table and the Storm Arrow jerked to the left, jostling Rhyme. "Shit."
    Ben's eyes went wide with alarm. "Are you all right, sir?"
    "Yes, yes, yes," Rhyme muttered. "What's that fucking table doing there? We don't need it."
    "I'll get it out of the way," Ben blurted, grabbing the heavy table with one hand as if it were made of balsa wood and stashing it in the corner. "Sorry, I should've thought of that."
    Rhyme ignored the zoologist's uncomfortable contrition and scanned the screen. "Large amounts of nitrates, phosphates and ammonia."
    This was very troubling but Rhyme said nothing just yet; he wanted to see what substances were in the dirt that Ben had dug out of the treads. And shortly these results too were on the screen.
    Rhyme sighed. "More nitrates, more ammonia – a lot of it. High concentrations again. Also, more phosphates. Detergent too. And something else . . . What the hell is that?"
    "Where?" Ben asked, leaning toward the screen.
    "At the bottom. The database's identified it as camphene. You ever hear of that?"
    "No, sir."
    "Well, Garrett walked through some of it, whatever it is." He looked at the evidence bag. "Now, what else do we have? That white tissue Sachs found . . ."
    Ben picked up the bag, held it close to Rhyme. There was a lot of blood on the tissue. He glanced at the other tissue sample – the Kleenex that Sachs had found in Garrett's room. "They the same?"
    "Look the same," Ben said. "Both white, both the same size."
    Rhyme said, "Give them to Jim Bell. Tell him I want a DNA analysis.