Achille sighed in exasperation. “It’s a shoeprint! My God, how could we have missed it?”

Rousseau lowered his bulk to a squat. “Damn it, you’re right.” Then he sprang up and pointed to a few prints on the pavement. “Look here and here, and then they stop; but all in the direction of the cesspit.”

“We have something, Rousseau. Our man left the sidewalk here, carrying the body. He stepped in the dung, stopped to scrape off the sole, and then continued on to the cesspit. Look, I can draw a line from here to where I picked up the cigarette butt.”

Thoughts whirled round Achille’s brain: Did he carry the body from one of these houses or did he use a vehicle of some sort? He couldn’t have carried it far; someone would have noticed. But there are no more footprints, and if he used a cart or wagon there are no marks, nothing discernible on the pavement.

Achille pulled out a ruler and measured the shoeprint and the length of the stride. They belonged to a very small individual. But the handprints were large, and he would have been strong enough to carry the torso, lift the manhole cover, and stuff the remains into the cesspit. Achille remembered the sergeant’s description of Toulouse-Lautrec: Monsieur’s legs are stunted, but he has the body, arms, and hands of a normal man with better than average strength.

“Gilles,” he cried, “I want you to photograph something up here.” Then to Rousseau: “I’m going to try to make a plaster cast of the shoeprint.”

“You’re the boss, professor, but have you ever made a cast of a turd?”

“There’s a first time for everything, Rousseau.”

The Morgue was a modern building erected on the Île de la Cité following the demolition of the medieval slums vividly described in Hugo’s Notre Dame de Paris. Upon entering, a visitor could look up and read the noble sentiments of The Republic: “Liberty! Equality! Fraternity!” Some might ponder a grim truth implicit in the revolutionary motto, for in this place the dead barons, bourgeoisie, and beggars were liberated from class distinctions and thus equal in fact rather than theory.

The Morgue was open to the public from morning to closing at six P.M. The morbidly curious with time on their hands came to gawk. They milled round the gas-lit corridors, gathering before immense plate glass windows, shivering in the cold air and inhaling the sharp odor of chlorine disinfectant, rubbernecking at the frozen macchabées—Parisian slang for corpses—whose naked bodies were propped up for display on steel slabs. Refrigeration was a recent improvement over the older preservation method: cold running water that gave the corpses a bloated, discolored appearance and chemicals that exuded an eerie, grayish-green mist round the bodies.

Many of the corpses on display were suicides fished out of the nearby river; some were murder victims whose bodies had been dumped by their killers. Regardless, all remained unidentified; the authorities hoped that viewers might recognize a loved one, friend, acquaintance, or co-worker. Indeed, some came to the Morgue searching for a lost relative, viewing the cadavers in the hope that identification might provide certainty and some closure to their personal tragedy. But, as with public executions, most just came for the show.

The Morgue attendant parked the meat wagon in a dark, narrow, cobblestoned passageway and unloaded the torso onto a trolley. He wheeled the corpse through a guarded back entrance closed to the public; Achille displayed his credentials and followed along with Gilles toting his camera and tripod. They passed through a murky corridor until they made a sharp right turn and entered a small, low-ceilinged dissection room.

The place reeked of carbolic disinfectant and formaldehyde. A bloodstained dissecting table stood in the middle of the room under a blazing gaslamp. Next to the table was a tray covered with neatly arranged scalpels, probes, forceps, clamps, and sutures. A mahogany and glass instrument cabinet occupied a corner of the drab, green-painted wall behind the dissection table. Two vividly colored folding anatomical charts with cutaway views—one male, one female—hung from the wall.

The gray-haired pathologist greeted them with a cold, bored stare. He had cut up too many corpses, a slave to routine like a factory worker who, over the years, had turned innumerable bolts on countless widgets. In contrast, Alphonse Bertillon was animated and enthusiastic.

Bertillon was an up-and-comer in his mid-thirties with a neatly trimmed beard, curious eyes, and a brisk manner. His brilliant career had begun ten years earlier, as a records clerk. Immediately recognizing the need for a better system of filing and organization, he pushed his new ideas on his superiors until they gave way from sheer exhaustion.

Young Bertillon was a force of nature, like a youthful Bonaparte telling old generals how to do their jobs. Having cleaned up the records system, he turned his attention to a better method of identification. Before long, the police had adopted his anthropometric system, incorporating multiple photographs, careful attention to features, and numerous, precise measurements. Now chief of the department of identification for the prefecture of the Seine, Bertillon was at the top of his profession, but he had not yet recognized the significance of fingerprints, a fact of which Achille was keenly aware.

His sleeves rolled up and ready to proceed, Bertillon smiled and extended his hand. “Pleased to meet you, Inspector Lefebvre. I’m Bertillon. I’ve heard good things about you from your chief. You’ve brought me an interesting case—a very interesting case indeed.” Bertillon spoke rapidly, leaping from sentence to sentence and thought to thought with the agility of an intellectual acrobat.

Achille admired Bertillon; he shook his hand warmly. “I’m honored, Monsieur. As you say, it’s an interesting case, and a tough one to crack.”

“Well, perhaps we can simplify things. Let’s take a closer look at the corpse. We have a moment while your photographer sets up his equipment, and there are some observations I can make before the doctor opens her up.” Achille followed Bertillon to the dissecting table, where the chief began his remarks with a theatrical flourish. Pointing a finger at the torso, he declared, “Keen observation and clear thinking can solve any mystery. We don’t chase our tails, we don’t waste time. For example, certain things are obvious to the trained eye. Your chief questioned whether this might have been a prank; some tipsy medical students stuffing a cadaver in the cesspit. But cadavers are embalmed prior to dissection, and the embalming fluid causes a grayish discoloration. That is not present here. On the other hand, if you look closely, you’ll notice a slight greenish spot on the lower abdomen. That is the first sign of decomposition. By that spot alone, I can place the time of death from forty-eight to seventy-two hours ago, and further examination can confirm my hypothesis and perhaps narrow it down. Do you know how long she was in the pit?”

“About forty-eight hours at most, Monsieur; the time between collections.”

“Ah then, whomever left the corpse would have known the schedule. And we can estimate the interval between the time of death and deposit in the cesspit. Then we’ll posit as to how the corpse was transported and from whence it came.”

Achille took out a pencil and pad and began scribbling notes.

Bertillon smiled at his attentive pupil and continued: “There are no visible signs of exposure to the elements, animals, or insects. Her skin is smooth and quite lovely, even with the pallor of death. We must look for scars, moles, birthmarks, tattoos or other identifying marks. Hmmm, nothing on the front. Let’s turn her over, doctor.” Bertillon and the pathologist rolled the torso onto its stomach, and then examined the neck, shoulders, back, buttocks, and thighs. “One small mole on lower right buttock; one smaller mole inner lower left thigh. We’ll measure them, and you’ll note them in the photographs. All right, doctor, let’s turn her right side up.”