The Burning Wire

I’ll bet. Terrible. The press is saying it’s probably an accident but . . .” He gave a skeptical laugh.
    “No, not accidental at all. We don’t know whether it’s a disgruntled employee or a terrorist.”
    “Anything I can do to help?”
    Arthur was a scientist too and somewhat more broad-based than Rhyme.
    “Actually, yes. I’ve got a fast question for you. Well, I hope it’s fast. We found some trace at the crime scene and it doesn’t match any substrata nearby. In fact, it doesn’t match any geologic formation in the New York area I’m familiar with.”
    “I’ve got a pen. Give me what you found.”
    Rhyme recited the results of their tests.
    Arthur was silent. Rhyme pictured his cousin lost in thought as he gazed at the list he’d jotted, his mind running through possibilities. Finally he asked, “How big are the particles?”
    “Mel?”
    “Hi, Art, it’s Mel Cooper.”
    “Hi, Mel. Been dancing lately?”
    “We won the Long Island tango competition last week. We’re going to regionals on Sunday. Unless I’m stuck here, of course.”
    “Mel?” Rhyme urged.
    “Particles? Yes, very small. About point two five millimeters.”
    “Okay, I’m pretty sure it’s tephra.”
    “What?” Rhyme asked.
    Arthur spelled it. “Volcanic matter. The word’s Greek for ‘ash.’ In the air, after it’s blown out of the volcano, it’s pyroclast—broken rock—but on the ground it’s called tephra.”
    “Indigenous?” Rhyme asked.
    In an amused voice, Arthur said, “It’s indigenous somewhere . But you mean around here? Not anymore. You could find a very minuscule trace amount in the Northeast given a major eruption on the West Coast and strong prevailing winds, but there haven’t been any lately. In those proportions I’d say most likely the source was the Pacific Northwest. Maybe Hawaii.”
    “So however this got to a crime scene it would have been carried there by the perp or somebody.”
    “That’d be my call.”
    “Well, thanks. We’ll talk to you soon.”
    “Oh, and Judy said she’s going to email Amelia that recipe she wanted.”
    Rhyme hadn’t heard that part of the conversation during the weekend out of town. It must’ve occurred on one of the beach walks.
    Sachs called, “No hurry.”
    After they disconnected, Rhyme couldn’t help but look at her with a raised eyebrow. “You’re taking up cooking?”
    “Pammy’s going to teach me.” She shrugged. “How hard can it be? I figure it’s just like rebuilding a carburetor, only with perishable parts.”
    Rhyme gazed at the chart. “Tephra . . . So maybe our perp’s been to Seattle or Portland recently or to Hawaii. I doubt that much trace would travel very well, though. I’m betting he was in or near a museum, school, geologic exhibit of some kind. Do they use volcanic ash in any kind of business? Maybe polishing stones. Like Carborundum.”
    Cooper said, “This’s too varied and irregular to be milled commercially. Too soft too, I’d think.”
    “Hm. How about jewelry? Do they make jewelry out of lava?”
    None of them had ever heard of that, though, and Rhyme concluded that the source had to be an exhibit or display that the perp had attended or that was near where he lived or where a future target was. “Mel, have somebody in Queens start calling—check out any exhibits, traveling or permanent displays in the area that have anything to do with volcanoes or lava. Manhattan first.” He gazed at the access door, wrapped in plastic. “Now, let’s look at what Amelia went swimming with. Your turn at bat, Rookie. Make us proud.”

Chapter 15
    CLEANING HIS LATEX gloves with the pet-hair roller—and drawing an approving look from Rhyme—the young officer hefted the access door and surrounding frame, still connected. The door was about eighteen inches square and the frame added another two or so inches. It was painted dark gray.
    Sachs was right. It was a tight fit. The UNSUB very likely would have sloughed off something from his body as he entered the substation.
    The door opened with four small turn latches on both sides. They would have been awkward to loosen with a gloved hand, so there was a chance he’d used bare fingers, especially since he’d planned on blowing up the door with the battery bomb and destroying evidence.
    Fingerprints fell into one of three categories. Visible(the sort left by a bloody thumb on a white wall), impressible (left in pliable material, like plastic explosive), and