Eliza finished the last verse of the last round of ' La Palomita' and was helped down from the cart by Pancho, her son. She had not missed a single note.

After Benigno, Lopez forbade the use of bullets, because they had not enough, and men were lanced where they stood. Particularly the men who had conspired with Benigno, but also, and sadly, the boy Paulino Álén, who came to the camp at San Fernando with a hole in his throat after the fall of Humaitá. He had tried to kill himself, and failed, so Lopez made a gift of it and finished the job for him. Stewart might have balked at this particular death or at another, but there was always the general truth of the war, and the honour of their cause. Benigno had conspired – there was no doubt about that. He had plotted to slip a knife between his brother's ribs, to hand over the country to the enemy, to hoard supplies, to deny marching men meat, to divert from the front line all kinds of fat bacon and shoulders of lamb, lard and cutlets and blood sausage and tripes. It gave Stewart satisfaction to see the man die, because there was justice in it. It gave him pleasure to see Mother Lopez caterwaul, the attitude she struck like The Virgin at the bottom of some savage cross. Also to see the tear seep out of the Little Colonel's green eye, before he turned to help his mother down from her cart.

Somewhere on the road Stewart had become a creature of Lopez. They all had. They could feel him in their blood. The terrible rapine that might seize a man, the frenzy of hacking and slashing – that was Lopez – the terrible urge to shit that might swell inside him when he had killed, so that soldiers dropped their kecks in the view of enemy fire there on the battlefield. It was not fear that made them so incontinent, but a madness of the body that filled them to bursting and demanded egress – of any kind: also carnal; the men being endlessly urgent and ignoble in that way.

Stewart, not being in the thick of it for the most part, kept his pants in order back and front. He confined himself to indifference – a narrow, whining sort of madness that might let a man die because he did not like the look of his ugly face. A civilised, smirking sort of thing, which stepped through the heap of enemy wounded and slit this, or that, throat. These were all pleasures. And he knew that once they slipped out of him, he could never call them back.

As the personal doctor of II Mariscal Lopez, Stewart lived close to the abrupt gesture; a wave of the hand that could kill a man. He tried not to fawn. He opened his medical bag with decisiveness and closed it with a satisfying click. Then he became too careful about his bag. Then he became too casual about his bag. He left the bag behind, as he squatted in a manly, companionable way and daily checked the presidential feet, the calluses and the many small joints. He rubbed Lopez down like a horse, feeling the tendons where they joined the bone. He enquired after his digestion and went behind a tree to check his stools, which were always a matter for congratulation. He lifted his member and rubbed it with a chalk mixture, to give a more cosmetic consistency to the gonorrhoeal drip. He treated the body of Lopez with cheerful hands. Not to do so endangered not only his personal health, but also the health of every man there, not to mention the well-being of the entire region of the Rio del Plata.

And sometimes, when he sat with Lopez talking about the need for heroes or the mechanising tendency in modern life (his foot idly tapping his doctor's bag), Stewart thought him the sanest man in the world.

In Tacuati, the straggling army bunched up to a halt, and they stayed for a week. There was an estancia there: a horseshoe of sheds around an open courtyard where Lopez sat at a table, and wrote. Then he sat back and looked at his notes. He talked to a queue of men and seemed to hand down judgment. Then he waved them away. He arranged the papers in front of him. He placed them in particular patterns. From time to time, he burned one.

There was no other madness.

Eliza encouraged the feeling of respite. She managed to give the place the atmosphere of a small spa. There was a little spring in the courtyard, and she drew wooden beakers of water from it, which she handed to the men herself; saying how restorative it was and extolling the pure heights from which it came. There was food, too, from the barns. And though they lived in uncertainty, there were things a man had not had, or heard, in some time, such as the sound of rain on his roof, for example, that lulled Stewart into an afternoon ecstasy of remembrance.

He was housed, for the duration, next to Eliza's quarters – a sympathetic billet: ever since they stopped, Stewart was fighting a sharp fever that followed its own clock; he could never tell what time he would be weak or clear-headed, and what time he would be stretched. It was a small, pungent room with no window and one rotting door. Where the dividing wall reached for the roof, there was a blessed, blunt triangle of open space; a dark gap through which the sounds of Eliza's 'drawing room' came to him as he lay on the floor. What a Babel! He would wake or drift to the sounds of her sons, speaking French to their Mama, or Spanish to each other, or Guarani to the men. Once, Stewart thought he heard German or something like it – Swedish perhaps -something guttural and rational and quite gorgeous that was telling him to lie down and keep his clothes on. And once, a whole sentence in English, 'The book is on the windowsilp, that was the most beautiful thing he had heard in a long time.

The girl lit a cleansing fire in his doorway and it flamed in the daylight, weakly orange, while the yard beyond buckled in the heat. Stewart saw things in the flawed air that he decided to tell no one about: not the girl, not Venancia, not his aunt, not his mother, not Eliza on the other side of the wall. He would tell no woman about these things that he saw. And he longed to rest his eyes on Eliza's boys, who stayed constant, all of them, and easy, through the haze.

Stewart could tell that they were fine young men, and very proud. Eliza had a certain way of sitting or being that could halt them at the mere sight of her – because of course they worshipped her, as boys do, and she adored them in return. Their father scattered them when he came into the room, but he too was indulgent and patient and kind. There was nothing degraded about this household. There was nothing that Stewart could sense of darkness, even when all was dark around him and his own death seemed as close to him as the family on the other side of the wall. Then closer. His own death scrabbled in the high triangular gap – he could smell the coming rot, he could see the long, black fingernails sneak in over the stone.

'Will you take a cup of coffee, my dear?'

It was hard to tell how sick or well he was when sentences like this fluttered down to him. Coffee? He must be dying. He looked at the girl as she dipped a rag into some water and wiped his chest. The rag, the water, the girl: these things were real. The coffee could not be real. He must be careful about coffee. He must stay alive.

Then he smelled it.

And Stewart decided that it was all real, in a way. Because the gods can make for themselves all kinds of felicity. The ease with which they run around, and chat and shout. The freedom they have. The lovely, ordinary nature of it all.

'Take your shoes off, my dear, and put your feet on this,' said Eliza, the cannibal. Eliza the evil one. Eliza who rushed, pregnant, into Humaitá to fling herself at II Mariscal's feet and say, 'Why does your brother Benigno hate me? Why does he insult and humiliate me like this? Why?'

But Stewart was delirious, and death crouched between the thatch and the wall. Death was a nest of insects; a thick, seething, black triangle, all shiny and heaving and trickling down the wall to crawl over him. And he itched and whined in the straw while from next door came the sound of a stool being set down.