“You’d be amazed at the things you can learn from hair,” he starts. “Hair evidence has figured quite prominently in some very high-profile cases throughout history. For instance, an analysis of hairs from Napoleon’s body revealed that he may have died of arsenic poisoning. Hairs that were connected to the anthrax mailing several years ago were analyzed with the hope they would implicate a scientist named Bruce Ivins at Fort Detrick in Maryland who was the primary suspect, but they weren’t a match. The scientist then committed suicide, leaving that hair evidence as one of the biggest puzzles in the case.”
Arnie pauses a second and a twinkle appears in his eye, letting me know the best is yet to come.
“On a more abstract level there is a rumor that hair samples collected in the Pacific Northwest prove the existence of a Big Foot type creature.”
Ah yes, my distant relatives.
“And there are some who believe that redheads are actually alien-human hybrids.”
Realizing that Arnie has now donned his foil hat, I try to steer him back on track. “I’d love to have you show me how you do hair analysis. I need to learn and it sounds like you really know your stuff.”
“Sure.” He brightens and stands a little straighter, puffing his narrow chest out so that he resembles a bird. If only Hurley were so easy. Arnie glances at his wristwatch and says, “We probably have time to do a quickie now if you want, before Izzy comes in.”
As the double entendre hits him, his face turns Day-Glo red and his glasses start to fog over.
“A quickie it is then,” I say, smiling.
For once, Arnie is speechless. His mouth opens and closes a few times, and he stammers out a few unintelligible syllables before turning away. He spends a moment zipping the body bag closed and cleaning his glasses off. By the time he’s done, he seems to have recovered. “Come on up to my lab,” he says, “and I’ll give you a crash course on hair analysis.”
“I’ll meet you there in a minute. I need to make a quick trip to the ladies’ room first.” This is a lie but I need to fetch Hurley’s hair from my purse and I don’t want Arnie to know that. I scoot back to the library, take the paper-wrapped hair from my purse, and shove it into my pocket. As I dawdle long enough to equal a bathroom trip, I brace myself for what lies ahead, wondering if I’m about to commit career suicide.
Chapter 10
Arnie’s lab area is located on the second floor of the building and is accessible only with a key card. As I make my way up the stairs, I ponder the potential implications of what I’m hoping to do. What if the hair I have matches the one found on Callie’s body? Where do I go from there? Can I believe Hurley? Can I trust him? Or am I letting my hormones get the better of me?
Arnie’s lab is an amazing demonstration of efficiency and order. The room looks smaller than it is because it’s jam-packed. Across the room from the entrance is Arnie’s small desk, which sits perpendicular to the storage cabinets lining the far end of the left-hand wall. The right-hand wall contains a long, equipment-covered counter full of machines, microscopes, analyzers, and other lab paraphernalia, with more storage cabinets mounted overhead. I find Arnie standing near the middle of this counter and he waves me over.
“This is a comparison microscope,” he says, pointing to the device in front of him, which looks like two microscopes joined at the hip with a double eyepiece centered between them. “It allows you to examine two objects side by side to look for differences and commonalities. For instance, I could have compared the hair we found on Callie’s body to one of her own hairs to try to determine if it was hers or the killer’s. I didn’t, because the evidential hair is coarse and black and hers are fine and auburn so the sources are obviously different. If the evidential hair wasn’t a human hair—it is, and I’ll explain how I know that in a second—I can look for a match in one of my reference books, or examine it next to sample references for different animal species: dogs, cats, horses, cows, etcetera, until I can determine what it came from. While an animal hair might not point directly to a given suspect, it can be useful in placing someone at a crime scene.”
He pauses, reaches up, and plucks a hair from his own head, wincing as he does. I’m not sure if he’s grimacing because of pain, or if it’s because his own hair is rapidly thinning on top, a fact I suspect he compensates for with his ponytail.
He cuts a segment of the hair and puts it on top of a glass slide. “We typically fix hairs as a wet mount using a drop of glycerin,” he explains, and after grabbing a nearby bottle, he unscrews its top and uses the attached eyedropper to apply a drop of a clear, viscous liquid to the hair. Then he places a cover slip atop the mount, causing the glycerin to spread over the entire sample. He positions the prepped slide on the bed of a nearby single stage microscope and turns its light on. After removing his glasses and positioning them atop his head, he looks through the eyepiece and adjusts the focus. When he’s done he steps back and says, “First let me give you a crash course on hair structure. Take a look.”
I bend down and peer through the scope.
“You’re looking at the hair magnified one hundred times. You should be able to see three basic layers. The outer layer is called the cuticle—that’s the part that looks like overlapping fish scales. It tells me what species the hair came from because each animal has a slightly different pattern. The dark line through the center of the hair shaft is the medulla, and between it and the cuticle is the cortex, which is where you’ll find tiny cells that contain whatever pigment colors the hair. How that pigment is distributed can vary from person to person and can sometimes be useful in matching a hair to a particular owner.”
I stand up and blink several times to adjust my focus. “You need a root to get DNA from a hair, right?”
“Yes, you do. But there is a lot of information you can get without the root. You can compare a hair to known samples for similarities. You can tell if a hair was cut off or pulled out, whether it’s human or animal in origin, and, if it is human, you can usually tell if it’s Negroid or Caucasian and where on the body it came from. Age might be discernible to some degree since infant hair is typically finer, but that can be a little iffy. With the right equipment you can also map out a dateline of exposure to certain poisons and elements by analyzing the hair shaft in small increments. But while we can compare color, structure, source, and length to determine if a given hair is consistent with a known sample, without a root it’s not as distinct an identifier as say a fingerprint or DNA.”
He walks over to a cabinet, opens a drawer, and removes a small cardboard box labeled with Callie Dunkirk’s name. Inside the box is a paper envelope with a slide in it. “This,” he says, proffering the slide, “is the hair from Callie Dunkirk’s wound.” He carefully removes the slide from the paper envelope and positions it on the left stage of the comparison microscope. He then switches the slide that holds his own hair to the right stage of the scope. After peering through the binocular eyepiece and making some minor adjustments to the focus, he stands aside and gestures for me to step in. “Take a look.”
It takes me all of a second to determine the differences between the two hairs. They look nothing alike; not only is the evidentiary hair thicker and darker overall, its medulla is thicker, too. Plus the scale patterns on the two hairs are noticeably different.