And yet it was nothing compared to the night we spent in the rainforest. Having crept along behind Innocent and Caleb for what seemed hours, with the more or less invisible jungle dragging at my ankles, thighs, face, I was relieved when we finally stopped in – apparently – a tiny clearing. But that relief didn’t last long. Innocent told us to put on our waterproofs, unfurled a poncho-type sheet of plastic from his own pack and tied it between two nearby trees. Then he told us to crawl under it with him and go to sleep.

This crude shelter was supposed to do two things. First, the obvious: keep us dry if it rained. Second, and more importantly: catch that rain so we could drink it. That’s why he weighted down the middle of our roof with a stone. But – just our luck – it rained nothing but mosquitoes all night long. Their whining was a horrible white-noise accompaniment to all the other chirping, whooping, clicking, barking sounds that cut through it. Though the soundtrack had been a pleasant enough distraction in the day, its night-time counterpart was sinister.

What was out there?

What wasn’t?

I imagined green mambas climbing the vines, warthogs rooting through the leaves, leopards in the trees. Innocent had said we would detour to a nearby river for water in the morning: what if a crocodile was doing its own detouring towards us now? Even if nothing big got us, something small might have a go. Scuttling sounds nearby were undoubtedly hungry rats. And the constant drone of insects made my skin – where it wasn’t already itching – crawl. We’d been issued malaria tablets in London, and I’d been taking them regularly, but right now they seemed a laughably weak defence. Enveloped in darkness, with the jungle alive around me and a plastic poncho for a roof, I’d never felt more exposed.

At one point, despite there being no rain, lightning split the sky. Everything jumped bright for a nanosecond. Then it happened again, and again, and again, each burst like an X-ray of the canopy, the twine Innocent had used to rig up the poncho, the dead leaves spread out around us, the swirling mosquitoes, and Caleb beside me, the thunder rolling through us, his eyes as wide and terrified as mine.

19.

I didn’t sleep that night. Though I was exhausted beyond belief, the best I could manage was a flickering semi-consciousness. Every time I thought I was drifting off I was pricked awake again, either by something actually pricking me, or plain old fear. Innocent’s stillness suggested he didn’t have the same problem, but I’m pretty sure Caleb, like me, just lay there through the night, willing it to end. Dawn couldn’t come too soon.

As it was, Innocent got up when it was still dark, just. I don’t know how he judged it so well, but by the time we’d bustled ourselves ready the first bluish hint of morning was filtering down to us. I was famished and parched and my feet were sore in my boots when we set off downhill in search of the river. Innocent explained as we walked that countless streams and rivers criss-cross the jungle, thousands of strands of water weaving into tributaries that eventually knit into the mighty Congo itself. We would pick one up nearby, drink, and follow it north; apparently this stream cut quite close to our base camp in the end. He was trying to take our minds off the pain of getting going again, I know. I did the same by imagining the statistics – rainfall measurements, humidity levels, that sort of thing – Amelia would no doubt have contributed if she’d been with us. I hoped she and the others had made it back to camp OK and slept better than us.