unfamiliar with the new equipment. Now, by pure good fortune, he had found an assistant.
It took him no time at all to defeat the lock on the front door of the building with a set of tools from his glove compartment. Silently he descended the stairs. A sign with an arrow pointed to ORGANIC CHEMISTRY LAB II. The lab door had a window in it. Looking through, he saw long countertops crowded with Bunsen burners, Pyrex flasks and beakers, test tube racks, and triple-beam balances. This much he’d expected, but what surprised him was the quantity of computer gear in the lab-keyboards and monitors and boxy CPUs.
At the far end of the room stood the lab worker in the white coat, bending over a table. Mobius opened the door and entered, unheard. When he was halfway across the room, he rapped his knuckles on a counter, and the other person turned.
'What the hell? How’d you get in here?'
'The building was unlocked.'
'No, it wasn’t.'
'It is now.'
Mobius looked over his new friend. He was just a kid-early twenties at the oldest. Sandy hair, thin build, hard plastic goggles over his wide, alarmed eyes.
'What are you up to at three-thirty in the morning?' Mobius asked.
The kid took a step forward. 'Get the fuck out of here.'
'You’re a poor host.'
'I’m calling security.'
'No, you’re not.'
The kid reached for a phone. Mobius closed the distance between them, and in a quick downward arc his knife sliced through the lab coat and incised a shallow wound in the kid’s lower abdomen.
He expected shock and fear to incapacitate his victim immediately, but the kid surprised him, lunging at Mobius in a wild attempt at self-defense. Mobius stepped backward, stumbling, off balance for an instant, and the kid flailed with a looping swing that swept a row of flasks onto the floor with a shattering of glass. Then Mobius steadied himself and caught the kid a second time with the knife, slashing his thigh, and the kid collapsed, a surge of red dyeing his pants.
Mobius stared down. 'Don’t be a hero, asshole. It only costs you blood.'
The kid touched the two wounds and gasped, shaking all over, then lifted his head to gaze up at Mobius with eyes that were now utterly cowed.
'You plan to cooperate now?'
The kid nodded.
'No more bullshit?'
'No.'
'Fair enough. So tell me, son, what’s your name?'
His lips worked for a moment before he answered, 'Scott Maple.'
'You’re a student, I assume. Too young to be a teacher.'
'Grad student.' Another shudder worked its way through him as he looked at the widening stain on his clothes, the red pool on the floor. 'Christ, it won’t stop bleeding.'
'Yes, it will. The first cut is barely more than a scratch. The second one’s a little more serious, but you have only yourself to blame for that. You never answered my first question. What are you up to?'
'Research project. For my Ph. D. thesis.'
'On Easter weekend, in the middle of the night?'
'Deadline.'
'What’s the nature of this all-important project?'
'Analysis of carcinogenic environmental contaminants.' He spoke in a dull monotone, as if reciting a memorized lesson. 'Pesticide concentrations, industrial residue, vapor discharged from burning fossil fuels. I’m using bomb calorimetry-'
'Bomb what?'
'Calorimetry.'
'You make bombs?'
'Not exactly. I mean, it is a kind of bomb, but…Look, what the hell do you care?'
'Bombs interest me.' Mobius looked Scott Maple up and down. 'So are you calmer now? Are you lucid?'
'Guess so.'
'Good. Because I’ve got a job for you. I found this item.' He held up the canister in a gloved hand. 'There’s liquid in it. I want to know what kind.'
'Is it…something dangerous?'
'Probably. But you handle toxic substances all the time, don’t you? Pesticides, industrial residue. You just told me so.'
'I…yeah, that’s what I told you.'
'You have a gas chromatograph in here, I’m sure.'
Maple jerked his head in the direction of an oven-size box hooked up to a computer. 'There.'
'Okay, then.' Mobius tossed him the canister, and Maple caught it reflexively. 'Get to work.'
The kid struggled upright, holding on to a counter for support. By now the bright flush of blood on his lab coat and pants was fading. The flow had ebbed.
'You have safety masks available?' Mobius asked.
'Sure.'
'Give me one. You put one on, too. And put on gloves.'
Mobius donned his mask, then stood back, careful to keep his distance from the canister. Scott Maple kept talking nervously, aimlessly, as he started a software program on the computer linked to the gas chromatograph.
'Okay, okay. The chromatograph is a Hewlett-Packard 5890. The PC maintains a stable environment for the chemical separation process. Okay, so first I turn on the FID air and hydrogen. FID, that’s-'
'Flame ionization detection,' Mobius said.
Maple glanced up, startled. 'Uh, that’s right. Sensitive to zero point four five parts per million. Next we ignite the flame.' He pressed the ignition button on the chromatograph. 'It ought to register at least fifteen on the screen. Okay, there it is.'
'Stop saying, ‘Okay.’'
'Am I doing that?'
'You are.'
'Okay. I mean-I’ll stop. Now we just, uh, set the appropriate values.' On the computer, he chose Set Method, then set the temperatures of the injector, oven, and detector to their defaults. 'Check the status. Then we…we have to wait. Till it warms up, basically. Shouldn’t take long.'
'While you’re waiting, prepare the sample.'
'Right. The sample.' He studied the canister. 'How do I extract the contents if I don’t know what I’m dealing with?'
'How would you handle the pollutants you’re cataloging?'
'Use a pipette to siphon out a few drops…'
'There you go. And by the way, it would be a good idea to stop trembling. If this stuff is what I think it may be, you can’t afford to make any stupid mistakes.'
Maple drew a quick, shallow breath that pulled the face mask tight against his nostrils. His goggles were steaming up with sweat.
He opened the canister and transferred a few drops of clear liquid into an Erlenmeyer flask. When the gas chromatograph’s temperature reached 325 degrees Centigrade, he fed the sample into the injection port and initiated the run.
The details of gas chromatography had changed in the twenty years since Mobius had attended college, but the basic science was the same. The sample, heated to a gas, would travel into a column lined with silicone grease. The grease would absorb the gas molecules and release them at varying intervals, known as exit rates. Every compound had its own unique exit rate, a chemical fingerprint. When the exit rates of the molecules were
