'Oh, my gods,' said Angua. 'Have we got any bandages?'
The sky was a little white circle, high above.
'Where the hell are we, partner?' said Cuddy.
'Cave.'
'No caves under Ankh-Morpork. It's on loam.'
Cuddy had fallen about thirty feet but had cushioned the fall because he landed on Detritus' head. The troll had been sitting, surrounded by rotting woodwork, in . . . well . . . a cave. Or, Cuddy thought, as his eyes grew accustomed to the gloom, a stone-lined tunnel.
'I didn't do nothing,' said Detritus, 'I just stood there, next minute, everything going past upwards.'
Cuddy reached down into the mud underfoot and brought up a piece of wood. It was very thick. It was also very rotten.
'We fell through something into something,' he said.
He ran his hand over the curved tunnel wall. 'And this is good masonry. Very good.'
'How we get out?'
There was no way to climb back. The tunnel roof was much higher than Detritus.
'We walk out, I think,' said Cuddy.
He sniffed the air, which was dank. Dwarfs have a very good sense of direction underground.
'This way,' he added, setting off.
'Cuddy?'
'Yes?'
'No-one ever say there tunnels under the city. No-one know about them.'
'So . . .?'
'So there no way out. Because way out is way in, too, and if no-one know about tunnels, then it 'cos no way in.'
'But they've got to lead somewhere.'
'OK.'
Black mud, more or less dry, made a path at the bottom of the tunnel. There was slime on the walls, too, indicating that at some point in the recent past the tunnel had been full of water. Here and there huge patches of fungi, luminous with decay, cast a faint glow over the ancient stonework.[21]
Cuddy felt his spirits lift as he plodded through the darkness. Dwarfs always felt happier underground.
'Bound to find a way out,' he said.
'Right.'
'So . . . how come you joined the Watch, then?'
'Hah! My girl Ruby she say, you want get married, you get proper job, I not marry a troll what people say, him no good troll, him thick as a short plank of wood.' Detritus' voice echoed in the darkness. 'How about you?'
'I got bored. I worked for my brother-in-law, Durance. He's got a good business making fortune rats for dwarf restaurants. But I thought, this isn't a proper job for a dwarf.'
'Sound like easy job to me.'