The Broken Window

and parts of New Jersey and Connecticut.
    Only small amounts adhered to the knife handlebut Mel Cooper collected enough to run a sample through the gas chromatograph/mass spectrometer, which breaks substances down into their component parts, then identifies each one. This took some time. It wasn’t Cooper’s fault. His hands, surprisingly large and muscular for such a slight man, moved quickly and efficiently. It was the machines that plodded away slowly, performing their methodical magic. While they waited for the results Cooper ran additional chemical tests on another sample of the dust to reveal materials the GC/MS might not find.
    Eventually the results were available and Mel Cooper explained the combined analysis as he wrote the details on the whiteboard. “All right, Lincoln. We’ve got vermiculite, plaster, synthetic foam, glass fragments, paint particles, mineral wool fibers, glass fibers, calcite grains, paper fibers, quartz grains, low-temperature combustion material, metal flakes, chryso-tile asbestos and some chemicals. Looks like polycyclic aromatic hydrocarbons, paraffin, olefin, naphthene, octanes, polychlorinated biphenyls, dibenzodioxins—don’t see those very often—and dibenzofurans. Oh, and some brominated diphenyl ethers.”
    “The Trade Center,” Rhyme said.
    “It is?”
    “Yep.”
    The dust from the collapsed World Trade Towers in 2001 had been the source of health problems for workers near Ground Zero, and variations of its composition had been in the news lately. Rhyme was well aware of its composition.
    “So he’s downtown?”
    “Possibly,” Rhyme said. “But you could find the dust all over the five boroughs. Let’s leave it a question mark for the time being. . . .” He grimaced. “So our profile so far: a man who might be white or a light-skinned ethnic. Who might collect coins and might like art. And his residence or place of work might be downtown. He might have children, might smoke.” Rhyme squinted at the knife. “Let me see it up close.” Cooper brought the weapon to him and Rhyme stared at every millimeter of the handle. His body was defective but his eyesight was as good as a teenager’s. “There. What’s that?”
    “Where?”
    “Between the hasp and the bone.”
    It was a tiny fleck of something pale. “You could see that?” the tech whispered. “I missed it completely.” With a needle probe he worked it out and put it on an examination slide. He looked at it through a microscope. He started with lower magnifications, which are enough, 4 to 24 power, unless you need the magic of a scanning electron microscope. “Crumb of food, looks like. Something baked. Orange tint. Spectrum suggests oil. Maybe junk food. Like Doritos. Or potato chips.”
    “Not enough to run through the GC/MS.”
    “No way,” Cooper confirmed.
    “He wasn’t going to plant something as small as that at the fall guy’s house. It’s some other bit of real information about Five Twenty-Two.”
    What the hell was it? Something from his lunch the day of the killing?
    “I want to taste it.”
    “What? There’s blood on it.”
    “The handle, not the blade. Just where that fleck is. I want to find out what it is.”
    “There’s not enough to taste. This little chip? You can hardly see it. I didn’t see it.”
    “No, the knife itself. Maybe I can find a flavor or spice that’ll tell us something.”
    “You can’t lick a murder weapon, Lincoln.”
    “Where’s that written down, Mel? I don’t remember reading that. We need information about this guy!”
    “Well . . . okay.” The tech held the knife close to Rhyme’s face and the criminalist leaned forward and touched his tongue to the place where they’d found the fleck.
    “Jesus Christ!” He reared his head back.
    “What’s wrong?” Cooper asked, alarmed.
    “Get me some water!”
    Cooper tossed the knife onto the examination table and went to call Thom, as Rhyme spit on the floor. His mouth was on fire.
    Thom came running. “What’s wrong?”
    “Man . . . that hurts. I asked for water! I just ate some hot sauce.”
    “Hot sauce, like Tabasco?”
    “I don’t know what kind!”
    “Well, you don’t want water. You want milk or yogurt.”
    “Then get some!”
    Thom came back with a carton of yogurt and fed Rhyme several spoonfuls. To his surprise the pain went away immediately. “Phew. That hurt. . . . Okay, Mel,we’ve learned something else—maybe. Our boy likes his chips and salsa. Well,