Page 190 of The Light Fantastic (Discworld 2)

'If you're going to suggest I try dropping twenty feet down a pitch dark tower in the hope of hitting a couple of greasy little steps which might not even still be there, you can forget it,' said Rincewind sharply.

'There is an alternative, then.'

'Out with it, man.'

'You could drop five hundred feet down a pitch black tower and hit stones which certainly are there,' said Twoflower.

Dead silence came from below him. Then Rincewind said, accusingly, 'That was sarcasm.'

'I thought it was just stating the obvious.'

Rincewind grunted.

'I suppose you couldn't do some magic—' Twoflower began.

'No.'

'Just a thought.'

There was a flare of light far below, and a confused shouting, and then more lights, more shouting, and a line f torches starting up the long spiral.

'There's some people coming up the stairs,' said Twoflower, always keen to inform.

'I hope they're running,' said Rincewind. 'I can't feel my arm.'

'You're lucky,' said Twoflower. 'I can feel mine.'

The leading torch stopped its climb and a voice rang out, filling the hollow tower with indecipherable echoes.

'I think,' said Twoflower, aware that he was gradually sliding further over the hole, 'that was someone telling us to hold on.'

Rincewind said another word.

Then he said, in a lower and more urgent tone, 'Actually, I don't think I can hang on any longer.'

'Try.'

'It's no good, I can feel my hand slipping!'

Twoflower sighed. It was time for harsh measures. 'All right, then,' he said. 'Drop, then. See if I care.'

'What?' said Rincewind, so astonished he forgot to let go.

'Go on, die. Take the easy way out.'

'Easy?' .

'All you have to do is plummet screaming through the air and break every bone in your body,' said Twoflower. 'Anybody can do it. Go on. I wouldn't want you to think that perhaps you ought to stay alive because we need you to say the Spells and save the Disc. Oh, no. Who cares if we all get burned up? Go on, just think of yourself. Drop.'

There was a long, embarrassed silence.

'I don't know why it is,' said Rincewind eventually, in a voice rather louder than necessary, 'but ever since I met you I seem to have spent a lot of time hanging by my fingers over certain depth, have you noticed?'

'Death,' corrected Twoflower.

'Death what?' said Rincewind.

'Certain death,' said Twoflower helpfully, trying to ignore the slow but inexorable slide of his body across the flagstones. 'Hanging over certain death. You don't like heights.'

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