Caleb, who was thirty metres upstream and already just about out of sight, shouted, ‘What are you waiting for?’

Innocent took a deep breath to tell him, but before he could there was a rush of leaves and a yelp-scream and what we could see of Caleb through the foliage suddenly changed shape. Both of us sprinted towards him. On arrival, it seemed as if he’d collapsed mid-cartwheel. One of his green boots was wrenched awkwardly above his head, still firmly attached to his foot, beneath which the rest of him was writhing on the ground. He’d stepped in a snare. I was surprised to find myself genuinely worried he’d been hurt. But his ‘Get me down!’ was angry rather than agonised.

Caleb’s machete was on the ground in front of me. The snare was made out of a loop of paracord rigged to a log, itself cantilevered over a bent tree. I couldn’t quite work out the mechanics of the thing, but if how to set Caleb free? was the question, sever the rope had to be the answer. I fired off a quick photo for the record while Caleb was looking towards Innocent, then picked up the big knife and swung it at the knot: the log thumped to the ground, the treetop snapped upright and Caleb’s leg joined the swearing rest of him on the floor.

‘You OK?’ Innocent sounded concerned: did he think Caleb was about to blame him?

‘Of course I’m OK.’ Caleb brushed himself down. ‘I just …’ He trailed off. For a half-beat I thought he might be about to laugh: since he wasn’t injured, surely he could see the funny side? But his face hardened and aside from muttering a brusque, ‘Thanks,’ as I handed him back his knife it was pretty clear ‘funny’ wasn’t on his radar.

‘Dangerous, horrible,’ said Innocent, holding up the snare. ‘Many animals die this way. They do not have a friend to cut them down.’

‘I’d have freed myself eventually,’ Caleb muttered.

He might well have done so – the machete was probably within his reach – yet his lack of gratitude was irritating. I tried not to respond. But once he’d picked the leaves out of his hair and was ready to go again, I couldn’t help pointing back downstream and saying, ‘Right then, shall we head in the actual direction of the others this time?’ with a fake lightness in my voice. I wish with all my heart that I’d held my tongue; if I’d stopped myself from goading him, we might have avoided the awfulness of what happened later.

20.