Free Pushed Too Far: A Thriller by Ann Voss Peterson, Blake Crouch Page B

held out a hand. “I need a piece of paper.”
    She ripped a sheet from the legal pad in front of her and gave it to him.
    He held the lighter’s flame to the corner, and the paper caught fire. “Now paper is a solid, but if you look at the flame, it never touches the edge.”
    “So fire only burns fuel in gaseous form.”
    “Right. And the more readily the fuel converts to gas, the hotter the fire.” He pointed through the side window of her office into the station’s main room. “Like those cubicles.”
    She looked at the ratty old walls that had been around for much longer than she had. “Fabric burns hot?”
    “It’s the type of fabric, plus the filler and glue. Especially glue. Something like that or that old pressed-board paneling people have in their rec rooms? A fire trap in the making.” He pinched the flame on the paper’s corner between his fingers. “Don’t want to set off the alarm.”
    She eyed the sprinkler above her desk. “Thanks.”
    “Flame is fuel in a gaseous state burning in the presence of oxygen. It’s a gas - gas reaction,” he explained.
    “And smoldering is solid - gas?”
    “You’re a star pupil. But for a solid to burn, you need oxidation of the solid fuel in direct contact with oxygen.”
    “Okay, you lost me.”
    “Think of a cigarette. When you suck oxygen through the tobacco, the fire gets hotter, glows brighter. More oxygen equals a hotter fire. But when the cigarette sits in the ash tray, it is still burning.”
    “It’s smoldering.”
    “Right. And it can only continue to burn because the structure of the burning tobacco rolled in paper is porous and rigid enough to stay that way. So oxygen is in contact with the charred surface even when the cigarette is at rest and burning at a cooler temperature.”
    “How does that apply to human remains?”
    “A substance that doesn’t create a rigid porous char won’t oxidize, therefore it will not smolder and won’t be self-sustaining. A good example would be thermoplastics, which melt as they burn.”
    Again, she wasn’t following. “There weren’t any thermoplastics in the barrel.”
    “Of course, there weren’t. But the best fuel in the human body is subcutaneous fat.”
    “The fat layer under the skin.”
    “Yes. Like any oil, it burns fairly efficiently, producing a flaming fire. But first it needs heat to transform it from solid to liquid to gas.”
    “The fire generated by the accelerant.”
    “Sure. And there was plenty of oxygen in the outside air, but it isn’t self-sustaining without one more thing.”
    “A chemical oxidation. Smoldering.”
    “Exactly. Namely something porous and rigid. Think of oil lamps, the fat is the oil, but it doesn’t sustain the burn without a wick.”
    “Couldn’t the flesh be the wick? Or the bones?”
    “It can, but the human body is mostly water. It takes time for flesh and bone to dehydrate enough to burn. The accelerant would burn off too quickly to do more than damage the skin.”
    “Jane Doe’s bones burned.”
    “Quite extensively, but you weren’t just asking me about Jane Doe.”
    Lund stood up and flipped open the file from Nebraska. Leaning over the desk, he pointed at one of the photos. “You see this?”
    His head was only inches from hers. Trying not to notice, she stared at the girl’s lower calves and ankles where muscle was charred as well as the skin. In the close up shot, she could see a clear glimpse of bone. “The damage is worst at her ankles.”
    “And her wrists.” He pointed to another shot.
    Val took in the damage, then looked up at him. “So something acted as a wick on her lower legs and forearms.”
    “My guess? She was tied.”
    Val looked down at the poor woman’s damaged face. How frightened she must have been when she realized his plan. Tied, helpless, witnessing that look in his eyes and feeling the slashes, the searing barrel of the curling iron, the fire’s heat lick her skin.
    What kind of pain had she endured?
    She