The trail wound through some thigh-high growth, and crested a ridge. There were some sparse, stunted trees dotting the hillside, sucking a living out of the marshy soil. Nate and Gerald were peering into the fog, trying to make any kind of sense out of the blurred grey, when they heard the low rumble of a growl far off to their right.

'Did you hear that?' Gerald gasped.

Nate held up his hand for him to be quiet. There came another growl. The fog made it impossible to gauge the direction properly, but it was close enough to set their hair on end.

'This will do, right here,' Nate whispered, beckoning his cousin into a stand of heather at the base of a fir tree. They crouched down in the soft, rough foliage, and Gerald gratefully propped the shotgun up against the tree trunk.

'If we can hear it, it can hear us,' Nate added. 'That's all I need. Hand me your bag.'

Gerald shrugged off the backpack and handed it over. Nate pulled out a wooden cube no larger than a shoebox, and then another object, covered in cloth. Unwrapping it, he revealed a funnel-shaped piece of metal, much like the end of a trumpet, with a bend at the narrow end.

'A music box? What, you're going to play it a tune?' Gerald smirked. 'I think you spent too much time with those bloody snake-charmers.'

'Watch and learn,' Nathaniel replied as he fitted the narrow end of the horn into the top of the sandalwood box. He inserted a small handle into the side of the music box and started to crank it round. Gerald looked on in fascination, his curiosity winning over his sarcasm.

'Most of the larger, lone engimals are territorial,' Nate explained quietly as he finished winding up the box. 'They don't take kindly to challengers. The Boers use these things as decoys.'

There was another mumbling growl, low and menacing. In the grey, cloudy air it was hard to tell how close it was, or in what direction. Gerald took his small hip flask from his jacket pocket and took a swig of brandy. His fingers were shaking as tried to screw the top back on.