There was nothing wrong with any of this, though he found the massivity of his heart, imagined or real, sometimes affected his lungs. He could not draw breath any more, or at least not a proper, manly breath. It was the grief, he thought. He had heard men complain of it -a tightness in the lungs that eased itself only in tears and that had no pathology that he could see. It was just that, as the number of the dead grew, your lungs shrank. As if to remind a man what it was to inhale and so to live.

His stomach escaped this inventory because he did not think of it as belonging to him anymore, and so it might be any size at all. It might be as big as the wide world, or as small as a bullet lodged in your gut. Mostly, he tried to ignore it, so capricious was it, and independent, and mean. But then the hunger moved to his mouth, and this made him want to wrap his gums around things – all manner of things – in order to assuage it. Or he might, in opening a wounded man, catch a glimpse of his last meal, and find a jealous spittle flood his own maw.

It was not that they were famished. They had food -or some food. It was just not the right food. There was something a man craved to see on his plate, but could not name. And as the months went by the soldiers sat around more, and their eyes became more inward-looking and difficult and complicit with their own pain.

It was around this time that the story went about that Eliza ate the flesh of the dead. She said it tasted just like pork, but gamier – like the truffle-hunting boars you get in the Auvergne. Some said it was Brazilian flesh she liked – though there was little enough of that about – others said it was their own. The story was universally believed – it was the truffles that did it. You could not invent a detail like the truffles: besides, who among them had ever heard of the Auvergne? And the taste of gamey pork circled endlessly in their mouths; the wetness so bad they must spit as they thought of Eliza pulling a long strip of pale ham from an amputated joint. These were men who looked at their own arms now, during a long day in the trenches, and judged the ratio of lean to fat. And though there was a horror to it, they did not exactly blame Eliza her portion, so much as blame this gaping world, into which you threw bodies, perhaps your own body, as though the sky itself were starving.

Then, when she appeared, the cannibal thoughts had nowhere to land. Eliza was, in all the mud-coloured world, the most beautiful thing. And they ate her with their eyes.

But what of love? said Stewart's worried thoughts. What has all this eating to do with love? Of course he found the cycle of life here uncomfortably close. They all did. During the endless afternoons, his medical heap of discarded flesh was often raided by dogs, who might be shot as they worried their human spoils. The shot dogs were then eaten. Of course they were cooked first and this made a difference, but the closer a man got to the line the more important it was to maintain it. And what else would keep the line, but love?

He was not the only one who felt this way. There was a keen trade in priests, these days, or the priest-like – men with a mellow, melancholic wisdom that in peacetime would have tempted you to hit them across the back of the head with a shovel – they drew their pipes on other men's tobacco, and gave, in return, a wise sigh and a story, preferably one of woe. Stewart did not listen unless it was a tale of love, because although love still frantically concerned him (also fate and mischance), death did not trouble him at all. The last death he had cared about was Whytehead's, and Whytehead had died some years ago. It was hard to remember when. Before that first action at Riachuelo, or after? It was certainly before any of the big engagements of the war. Whytehead was missing all the fun. No, the last time Stewart had seen him, the band was playing ' La Palomita', and the crowd were cheering their heads off, and Whytehead was just standing there, looking at them all.

It was the morning after Stewart had, or had not, kissed Eliza Lynch; the morning the fleet was dispatched to break the blockade. The whole town stood in Plaza de Palma cheering, one more time, the Tacuari. With her now were the Paraguari, and five or six more, including the Ygurei, the Jejut, and the Salto Oriental. The captured Brazilian steamship Marques de Olinda was re-rigged with the national flag and it all looked so fine, and so very much his own, that Stewart forgot about fumblings with this woman or that. No man's heart can resist the tug of ships and, as they pulled slowly away, Stewart flung the stupid kiss, and all kisses, after them, as you might lob a pigeon; a flurry of muscle and emotion, which soared up to drift awhile in their wake.

'Huzzah,' he shouted, and he waved his very British hat. 'Huzzah!'

And Whytehead gave him a narrow look.

So he was almost pleased when, after a few weeks in the field, the news came of the man's death. The ships had engaged in the shallows of Riachuelo and the action had failed. The Jejuiand the Salto Oriental were lost, the Paraguarilaid helpless. The commander of the fleet, Commodore Meza had, wisely, stopped off in Humaitá to die of his wounds. And it was at Humaitá that Stewart heard the news that, upriver, the Arsenal had lost its chief engineer and the army their free supply of matériel. And he felt whatever thread tied him to Whytehead snap.

He was curious to find that there actually was a thread somewhere, like a tendon in his chest in which the connection he had to this man had been manifest. He was surprised to feel an actual sensation of loosening. The picture of the Fates was, he thought, quite just – their big shears cutting the threads of a man's life – because what the world feels when a man dies, even at a distance, is an unravelling.

The body was found in his tobacco barn and the story circulated that Whytehead had hanged himself from a beam there. His dinner doctors, Fox and Skinner, had diagnosed self-poisoning: he had taken an infusion of nicotine they said; a pesticide he concocted against aphids. Stewart knew he would do no such thing. It would mortify his sisters. And he sat down to write and tell them so. 'Dear Misses Whytehead,' he began. Thinking that the letter would never reach them. Wondering how much of their brother's money would ever make it to the Mile End Road.

In the months that followed, Stewart's thread theory, or tendon theory, was of some comfort to him. It was as though he had a little packet of humanity stored safely in his chest, and he occasionally patted himself there, as a man might check for his pipe, while around him the cholera came and with it all other kinds, shades, varieties and types of shitting – dysentery, typhoid, and the rest. He wondered why God had not designed for mankind a convenient plug. He thought, also, that if he saw another man with his pants stinking, he might kill him, just to save time.

In October the northern army had limped down from the Cordillera and there was little enough for Stewart to do. Only the minor wounded made it back, carried over that great distance by brothers, or friends, or even strangers -who must have been put out when Lopez shot their burdens as soon as they set them down, in order to purge the shame of the surrender at Uruguiana.

The general was shot first – which was the difference between Lopez and other commanders of men. There he goes, thought Stewart. My animal Mariscal with his animal war. He walked up the lines of the wounded and stared each man in the face, checking his eyes as the band played ' La Palomita'.

The great slaughter had begun, and it was years before Stewart cared again.

Then, in June of 1867, a man came up to him and spoke a sentence so clearly that Stewart wondered at the path this news had taken – it had travelled such distances to hit with precision the side of his head, where nature had placed an ear to receive it. The Doterelhad been let through in June with a new English envoy; perhaps the news had come in a letter that Venancia opened on his behalf. Was it her voice he heard through the man's face, as he came up to him in the middle of a busy afternoon and said, Ί am to tell you that Miss Steerat of Edingbur is dead.' It was news, he said, for Έ1 Doctor' – who indeed had an aunt called Miss Stewart who was by now long dead in Edinburgh as opposed to any other town. Where the news had come from, or who had paid for it, Stewart did not know. When he lifted his suddenly heavy face to thank the man, he had already turned to go.