Still, it brought home to them yet again how insane their opponents were. Ignorant fanatical disciples of a cruel desert cult, promised eternity in a paradise where sexual orgasm with beautiful houris lasted ten thousand years, no surprise they were so often suicidally brave, happy to die, reckless in frenzied opiated ways that were hard to counter. Indeed they were known to be prodigious benzedrine eaters and opium smokers, pursuing the entire war in a jerky drugged dream state that could include bestial rage. Most of the Chinese would have been happy to join them there, and opium had made its way into the Chinese army, of course, but supplies were short. Iwa had local contacts, however, and as they prepared for the assault on Nangpa La he obtained some from some military policemen. He and Bai smoked it in cigarettes and drank it as a tincture of alcohol, along with cloves and a pill of Travancori medicines said to sharpen sight while dulling the emotions. It worked pretty well.

Eventually there were so many banners and divisions and big guns collected on this high plane of the bardo that Bai became convinced that the rumours were right, and a general assault on Kali or Shiva or Brahma was about to begin. As confirming evidence he noted that many divisions were composed of experienced soldiers, rather than raw boys or peasants or women – divisions with extensive battle experience in the islands or the New World, where the fighting had been particularly intense, and where they claimed to have won. In other words, they were precisely those soldiers most likely to have been killed already. And they looked dead. They smoked cigarettes like dead men. A whole army of the dead, gathered and poised to invade the rich south of the living.

The moon waxed and waned and the bombardment of the invisible foe across the range continued. Fleets of flyers shaped like sickles shot through the pass and never came back. On the eighth day of the fourth month, the date of the conception of the Buddha, the assault began.

The pass itself had been rigged, and when its immediate defenders were all killed or had retreated south, the ridges guarding the pass erupted in massive explosions and poured down onto the broad saddle. Cho Oyo itself lost some of its mass to this explosion. That was the end for several banners securing the pass. Bai watched from below and wondered, when one died in the bardo where did one go? it was only a matter of chance that Bai's squad had not been in the first wave.

The defences as well as the Chinese first wave were buried. After that the pass was theirs, and they could begin the descent of the giant glaciercut canyon south to the Gangetic Plain. They were attacked every step of the way, chiefly by distant bombardment, and with booby traps and enormous mines buried in the trails at crucial points. They defused or set these off as often as they could, suffered the occasional missed ones, rebuilt a road and rail bed as they descended. It was mostly road work at great speed, as the Muslims gave ground and retreated to the plain, and only their most distant aerial bombardment remained, shots fired from around Delhi, erratic and hilarious unless they happened to make a lucky strike.

In the deep southern canyon they found themselves in a different world. Indeed Bai had to reconsider the idea that he was in the bardo at all. If he was, this was certainly a different level of it: hot, wet, lush, the green trees and bushes and grasses exploding out of the black soil and overrunning everything. The granite itself seemed living down here. Perhaps Kuo had lied to him, and he and Iwa and the rest here had been alive all the while, in a real world become deathly with death. What an awful thought! The real world become the bardo, the two the same… Bai hustled through his hectic days feeling appalled. After all that suffering he had only been reborn into his own life, still ongoing, now regained as if there had been no break, only a moment of cruel irony, a few days' derangement, and now moved on into a new karmic existence while trapped in the same miserable biological cycle that for some reason had turned into a One simulacrum of hell itself, as if the karmic wheel had broken and the gears between karmic life and biological life become detached, gone so that one fluctuated without warning, lived sometimes in the physical world, other times in the bardo, sometimes in dream sometimes awake, and very often all at once, without cause or explanation. Already the years in the Gansu Corridor, the whole of his life he would have said before, had become a dream mostly forgotten, and even the mystic high strangeness of the Tibetan plateau was fast becoming an unreal memory, hard to recall though it was etched on his eyeballs and he was still looking right through it.

One evening the wiregraph officer came rushing out and ordered them all to get uphill fast. A glacial lake upstream had had its ice dam bombed by the Muslims, and now a huge bolus of water was headed downstream, filling the canyon to a depth of five hundred feet or more, depending on the narrowness of the gorge.

The scramble began. How they climbed. Here they were, dead men already, dead for years, and yet they climbed like monkeys, frantic to move up the slope of a canyon. They had been camped in a narrow steep defile, the better to avoid bombs from the air, and as they hauled themselves up through brush they heard ever more clearly a distant roar like continuous thunder, possibly a falls in the ordinarily loud Dudh Kosi, but probably not, probably the approaching flood, until finally they came to a layback in the slope, and after an hour they were all a good thousand feet above the Dudh Kosi, looking down at the white thread of it which seemed so harmless from the broad nose of a promontory where the officers had regathered them, looking down into the gorge but also around them at the stupendous icy walls and peaks of the range, hearing a roar come out of the higher ones to the north, a healthy booming roar, like a tiger god roaring. Up here they were in a good position to witness the flood, which arrived just as night was falling: the roar grew to something almost as loud as a bombardment on the front, but all below, almost subterranean, coming through the soles of their feet as much as their ears, and then a dirty white wall of water appeared, carrying trees and rocks on its chaotic tumbling front wall, tearing the walls of the canyon right down to bedrock and causing slides down into it, some of which were large enough to dam the whole stream for a few minutes, before water poured over it and ripped it away, causing a smaller surge in the general flood. After the front of it had passed out of sight down canyon, it left behind torn walls white in the dusk, and a brown foaming river that roared and clunked at just above its usual level.

'We should build the roads higher,' Iwa noted.

Bai could only laugh at Iwa's cool. The opium was making everything pulse. A sudden realization: 'Why, it just occurred to me – I've been drowned in floods before! I've felt the water come over me. Water and snow and ice. You were there too! I wonder if that was meant for us, and we've escaped by accident. I don't really think we're supposed to be here.'

Iwa regarded him, 'In what sense?'

'In the sense that that flood down there was supposed to kill us!'

'Well,' Iwa said slowly, looking concerned, 'I guess we got out of its way.'

Bai could only laugh. Iwa: what a mind. 'Yes. To hell with the flood. That was a different life.'

The routemakers however had learned a good lesson without much loss of life (equipment was another matter). Now they built high on the canyon walls where they sloped back, cutting grades and traverses, going far up tributary canyons and then building bridges over their streams, also anti aircraft emplacements, even a small airstrip on one nearly level bench near Lukla. Becoming a construction battalion was much better than fighting, which was what others were doing down in the mouth of the canyon, to keep it open long enough to get the train down there. They could not believe their luck, or the warm days, or the reality of life behind the front, so luxurious, the silence, the lessening of muscle tension, lots of rice, and strange but fresh vegetables…