"What do you mean, he won’t be in ’til noon?" I asked in exasperation. "I had an appointment with him for nine."

     Margo Davis half laughed and half frowned. "You didn’t have an appointment with him. You have an appointment with me."

     A girl who talks to me like that rates a second look: about 35, curly, dark-blonde, middle-length hair framing a reasonably attractive and sympathetic face. She wore tennis shoes, faded jeans, and a thick, oversized T-shirt commemorating "Sunburst 1992, Montego Bay." Outwardly, she was a female version of me.

     "Did Dr. Ashton tell you what project I will be working on?"

     "No. But it don’t make no difference!" she retorted, apparently using the double negative for emphasis, although she did sound a little Cracker. "You don’t know the techniques yet."

     "Why won’t it make any difference?" I asked. "I know a lot of analytical techniques already."

     "But you don’t know how to ‘Grind ’n’ Bind’ yet, and that’s what I’ve got to teach you." My mouth dropped open. "I teach everyone that comes in here — the high school students and the visiting professors." With that kind of repartee, she could have doubled as a bar maid at Captain Walley’s.

     I acquiesced and let Margo Davis teach me the "Grind ’n’ Bind." We took a couple of mice out of a cage, put them in a plastic tube full of carbon dioxide to make them lose consciousness, cut off their heads, opened their skulls, took out their brains, and ground them up in a miniature Waring blender. That was the "grind." Then we centrifuged the soup to get nerve membrane fragments, incubated them with a radioactive drug and then caught the membrane-bound drug on filters. That was the "bind." The drug bound tightly to certain "receptors" in the nerve membrane and to nothing else. We put the filters into vials and took them to the scintillation counter that read the amount of radioactivity.

     The experiment was so simple, it felt like going back to kindergarten. Chatting with Margo, I learned that she was a dyed-in-the-wool Miamian and had worked with Ashton for 14 years. Her husband worked for the phone company. She was Ashton’s only technician and was responsible for everything from his daily experiments to mothering his graduate students.

     Over the years, she’d helped about 30 graduate students, four of whom had stayed on to do dissertations. She indicated that none of them would have made it without her help. With Margo’s help, I mastered the Grind ’n’ Bind by 11:30, a full half-hour before Ashton showed up.

     Ashton politely wished us a good morning and sequestered himself in his office. No welcome aboard, Ben Candidi. No pep talk about how the drug receptors are responsible for opening ion channels in membranes to make the nerves fire. No in-depth conversation about how drug binding to receptors makes it easier or harder for the ion channel to open. No inspirational message about how psychoactive drugs make it possible for people suffering from depression to lead normal lives. Just a closed door.

     Margo sensed my disappointment and indicated this was par for the course.

     "We usually don’t get around to figuring out the project until the student’s been here a week. And you need more training. We’ve got a rule that the student has to reproduce my results in a system I’m working on before they can go out on a new project."

     "But I learned the technique today and — "

     "Ben, these filtration assays all have to be done the same way. Now come in tomorrow afternoon and we will do some experiments on the GABA receptor, and I’ll show you how to use the scintillation counter."

     So much for my first day in the lab.

     I was upset until it occurred to me that Margo might be a big help in identifying the toxin Ashton used to kill Cooper.

     That afternoon, I checked my box and found a note to "Call Steve," with no phone number. Steve Burk told me to come over to the M.E. Office at 5:30. When I reported for duty, he told me to change some columns on the HPLC, and give the GC-Mass Spectrometer a shakedown. When I was an hour into the job, he gave me a bill for service, which he asked me to sign. It was a nice typeset invoice. Bold letters on the top proclaimed:

CANDIDI SCIENTIFIC INSTRUMENTS

Repair and Maintenance

     followed by my post office box number. At the bottom was my social security number and "Terms: 30 days net."

     They had typed in a statement for 20 hours of work. I signed it and handed it back without comment.

     Burk handed me a couple of pads of blank forms and said, "Hold onto these for future use. I have to go home now. Please arrange to come back and do another ‘twenty hours’ next week. You can leave any time."

     So the M.E. Office was giving me full pay for light duty.

     Heavy course work forced me to postpone my next grind ’n’ bind session with Margo. But I took it in stride, learning to give smart answers about "single channel conductance," "channel open probability" and the "Hodgkin-Huxley-Katz Theory" of the nerve action potential.

     I spent many hours in the library filling in the cracks between the lectures and the reference books. Dr. Gordon Taylor told the class, "As you approach the frontiers of science, the textbooks will prove less useful. And we don’t want you whining about an exam question not being covered in the book."

     It wasn’t hard when you think of the cell as little factories and proteins as little machines. In Biochemistry, I learned how the class of proteins called enzymes do their jobs efficiently, binding their specific "substrate" molecules, tightly and specifically, and chopping them in two. Some enzymes join two substrate molecules to build a bigger and more complicated molecule. I began to understand how drugs can bind where the substrates should, and block the reactions. I learned from Dr. Kozinski how one enzyme kicks another enzyme into high gear by chemically tagging it with phosphate — social behavior among enzymes. You can’t run a factory without someone getting bossed around.

     The biochemists admitted that the DNA in the chromosomes is the ultimate boss, the factory manager. Next semester in Molecular Genetics, we would learn the secrets of genes. Kozinski said that some day it might be possible to reverse the mutation in sickle cell anemia and start the cells making perfect hemoglobin.

     During these first hectic few days of the Ph.D. program, I got a good study routine going. When not in class, I was in the Medical Library across the street from the Medical School. I picked out a carrel which commanded a good view of the second floor and was also convenient to a pair of couches. I stored my computer in a rented locker. What more could a guy ask for? Books, journals, air-conditioning, a convenient wall socket to plug in my computer and a good perch to watch the girls from. While thinking about perfect fits between substrate and enzyme, I sometimes lapsed into daydreams about the girl who would be a perfect fit for me.

     The girls ran the whole spectrum from first-year nursing students, med students, graduate students, through working physicians and assistant professors. The nursing students seemed a little young for me.

     The med students were easy to identify. With a little practice, I could even figure out what year they were in. The first year variety were noisy and nervous, and always hung around in groups. It would make me restless, too, having to learn the Latin names for all those bones, muscles and nerves without any apparent purpose. The second-year med students were more at home, scattered around the library, reading textbooks, silently mouthing words for rote memorization and systematically transcribing pages of textbook onto flash cards. They also mastered the art of sleeping in the library, sprawled out on the couches.

     The third- and fourth-year med students were in clinical rotations. They wore white jackets, pockets stuffed with loose-leaf notebooks and file cards for ready access to important information. They entered the library with a purposeful demeanor, usually walking directly into the stacks in search of an article. The more advanced the med student, the more worn out they looked. One night I looked up from my book to see the girl of my dreams walking by. She was probably a medical sophomore. She was gone before I thought of something to say.

     One afternoon I dropped into the graduate student room while Maria Mendez was on the phone, talking in Spanish. I sat down and cracked open a book, but it was impossible to ignore her conversation. Her mom was complaining that her sister was causing problems again. Maria ended the conversation early and plunked down into a chair.

     "You know, Ben, sometimes I almost feel like giving up. Ilsa is throwing fits because we can’t give her a fancy Quince. We’ll be lucky if we have a thousand dollars at the end of the month."

     In Anglo culture it’s "sweet sixteen," but down here it happens a year earlier. Special banquet halls are designed to take care of the parties and to take care of your bank account in the process. With the white dresses, the invitations, the food and photographers and everything, a Quince can cost $5,000.

     "I know what you mean," I sympathized. "It’s like the fancy wedding that no one can afford."

     "And Mama and I are worrying about Papa. He shouldn’t be working with his weak heart. And he won’t listen to the doctor and stop smoking cigars."

     She stood up and walked over to the window, perhaps to hide her face.

     "Talk to your other sister. You told me she’s nineteen. Maybe she can talk some sense into Ilsa."

     "Lourdes is just as loca as Ilsa. I told her Lazaro was no good for her. She thinks he’s going to be a big businessman, but at his rate, it’s going to take him eight years to get out of Miami-Dade Community College. And he spends all the money he makes at Dixie Super-Check on that stupid car. He loves that dumb Camaro more than he loves her. Even now."

     "Even now?"

     I shouldn’t have asked. Maria was silent for a long time, then her shoulders caved in with a sigh. "She’s two months pregnant."

     I got up and steadied her trembling shoulders with my hands, and found some words of encouragement. She should take a hard line on the Quince and should give some good-sisterly advice to Lourdes. I turned her around, dabbed her eyes with the collar of my polo shirt and gave her a brotherly kiss on the cheek — which she answered with a kiss on the lips. For an awkward moment, it threatened to become passionate. I’m not one of those guys who can have a frivolous affair with a serious girl. I promised to help her with the Membranes Course, which I did. Several months later, she returned the favor in a big way.

     I always tried to make us a foursome by including Grant Shipley and Sheng-Ping Chow. The volleyball champ from Peking Medical College needed lots of help with English, and our conversations served as short tutorials. I told him to spend some time watching television in the medical student lounge. Television makes your brain porous, and he could learn English by osmosis. But he spent every spare moment on a lab rotation. I admired his zeal.

     I shared a lot of laughs with Margo during an afternoon Grind ’n’ Bind session later that week. She said I was "getting pretty good" and that Ashton might give me a project next week. He was always holed up in his office. That was fine with me — not having him around while I joked his neurotoxin secrets out of Margo.