Silius hung back for a moment, watching as Caesar mounted the last ramp leading to the Capitol. His stride was energetic, resolute — a soldier’s stride. He had weathered another attack and, if anything, seemed more vigorous for it. Perhaps even now he was convincing himself that he could overcome this illness, just as he had overcome everyone and everything that had ever blocked his path.

The temple was open and the statue of Jupiter was visible inside. In reality only the head could be seen at first, but as one walked up the ramp, the perspective changed and, little by little, the god revealed his chest, his arms, his groin, his knees. It was an ancient statue, its features harsh and angular, its beard stiff. An effigy designed to be frightening, or at least to inspire awe. Jupiter was flanked, in the chambers on either side, by statues of Minerva and Juno.

The two men approached the altar, where a small crowd was waiting. Some of them were senators, including several of Caesar’s friends. Others, like Antony, were missing. His duties as consul must have been occupying him elsewhere.

The second and third rows were filled with commoners, all hoping for their share of the flesh after the sacrifice. The members of the Flamen College of Pontiffs, in full ceremonial attire, filed out from the temple door.

As soon as the Pontifex Maximus, his face still hidden from sight, reached the altar, the sacrificial animal was brought forward: a calf, three or four months old, with budding horns. One of the servants accompanying the animal carried an axe, the other held a tray of mola salsa, a mixture of salt and emmer flour, the food of the Romans’ frugal ancestors. Caesar picked up a handful and sprinkled it on the calf’s head. At his signal, the heavy axe fell on its neck with a clean stroke. The head rolled to the ground and the body collapsed, blood pumping out.

Ever since his return from the last war in Spain, Silius couldn’t stand the smell of blood, not even if it came from an animal. He tried to take his mind off the scene by thinking about something else, but all he could come up with was the troubling news arriving from Syria and Spain, neither of which was completely pacified yet. He glanced up at the sky, which was getting darker and darker by the minute without dissolving into rain. Meanwhile, the thunder continued its low, distant roll over the mountains that were still capped with white.

The servants turned the calf on to its back and sliced open its chest and stomach so the haruspex could examine the bowels and interpret the omens.

Caesar was just a few steps away, seemingly absorbed in the scene, while his mind followed other paths. His illness. The expedition against the Parthians. The future of the state. Enemies still living, enemies who had died, the ghosts of the martyrs of the republic who tormented him still.

All at once, his gaze chanced upon on the calf’s lifeless head. He’d been careful to direct his eyes elsewhere, but that’s where they’d been drawn, against his will.

Silius glanced over at him at that moment and their eyes locked. Both were thinking of the same thing: of Pompey’s head, of the fixed stare of their great, defeated adversary. ‘They had it coming,’ was what Caesar always said, time and time again. True, he’d offered Pompey an out, more than once, and Pompey had always refused, but the thought of the decapitated head of the great Roman preserved in brine was something that would never cease to weigh heavily on his heart.

And his mind.

Gossips had even been known to suggest that the young Egyptian king Ptolemy XIII — the husband and brother of Cleopatra — had relieved Caesar of a thankless but inevitable task by killing Pompey himself, thus giving Caesar the chance to publicly spill a few tears over his former son-in-law.

The haruspex had plunged his hands into the bowels of the sacrificial calf and was searching through the steaming entrails. His confident gestures suddenly grew confused and dismay was apparent in his eyes. He seemed to be on the verge of panic and the onlookers were becoming aware that something had gone wrong. Caesar noticed as well and drew closer to the haruspex. Silius also approached, overcoming his revulsion for the blood and the stench of slaughter.

‘What is it?’ Caesar demanded of the haruspex. ‘What do you see?’

The ashen-faced priest stammered, ‘The heart. . I can’t find the heart. It’s a terrible omen.’

‘Not another word from you,’ growled Caesar.

Setting aside his toga and rolling his tunic sleeves up past his elbows, he sank his hands resolutely into the animal’s chest cavity. A dark gurgle and, for an instant, Silius thought he saw an anguished look of uncertainty in Caesar’s eyes. But only for an instant.

Caesar had a basin of water brought to him so he could wash his hands and, as the water turned red, he said, ‘It was covered with fat and was a bit smaller than normal. This man is incompetent and that makes him dangerous. Get rid of him. Now burn it all,’ he ordered, to the consternation of the populace watching the sacrifice. ‘The gods mustn’t be kept waiting.’

He had another basin of water brought, finished washing and used the white linen cloth the servant held out to dry his hands.

Silius walked away and went up the steps towards the sanctuary portico. From there he could see the crowd of onlookers below, scattering and going off in different directions. A fire was lit on the altar and the animal was cut to pieces and burned in the flames. But that was of no interest to Silius; he wanted to be certain that the litter had been brought to the appointed place and that the men were alert and ready if needed.

He lingered, turning towards the interior of the temple, as if he meant to pay homage to the gods of the Triad standing straight and still in the shadows, when his attention was caught by something glittering on the purple cushion at the feet of the statue of Jupiter, so tall its head nearly touched the ceiling. It was a golden crown. A scroll carved into the wooden base proclaimed: TO JUPITER, THE ONLY KING OF THE ROMANS.

He glanced back at the altar, where Caesar was presiding over the traditional rites of purification which ended the sacrificial celebrations, then slowly walked down the steps again.

The clouds still hid the sun, parting here and there to show wisps of blue, only to close back instantly to grey. Silius waited on the south side of the steps until the Pontifex Maximus had finished saying his goodbyes and then accompanied him back to the Sacred Way. The litter followed at a respectful distance.

From the Forum they could hear the buzz of the crowd that had begun to gather for the day’s business: shouting from vendors in the shops and pedlars on the street, a magistrate at the Rostra calling for people’s attention.

‘If you found the heart, why didn’t you pull it out?’ asked Silius.

‘Rooting around in the bowels of a butchered animal is disgusting and there was no need for it. The animal was alive, so it must have had a heart. Do you know the story of Anaxagoras’s calf?’

‘I don’t believe I do, Caesar.’

‘Back when Pericles was just entering politics, there was a calf born in Athens with a single horn. Pericles consulted a seer, who told him that it was an omen. It meant that the people’s party, which had two leaders, Pericles and Ephialtes, would soon be led by one man alone and that man would be Pericles. Anaxagoras the philosopher was immediately summoned to give his interpretation. He opened the animal’s skull straight away and examined its brain, where he found gross abnormalities. He explained the true reason why the calf was born with a single horn: because of a physical deformation. There’s always an explanation, Silius. And if we can’t find one, it doesn’t follow that we’re looking at a miracle, but simply at our own ignorance and inadequacy. All it means is that we are unable to understand the reasons for whatever has happened.’