He considered the air around the door itself, how it might best be twisted into weird shapes so that the door existed in another set of dimensions entirely.
The door sat there, defiantly solid.
Sweating, his mind beginning the endless walk up to 187 the blackboard in front of the grinning class, he turned desperately to the lock again. It must be made of little bits of metal, not very heavy —
From the grille came the faintest of sounds. It was the noise of wizards untensing themselves and shaking their heads.
Someone whispered, 'I told you—'
There was a tiny grinding noise, and a click.
Rincewind's face was a mask. Perspiration dripped off his chin.
There was another click, and the grinding of reluctant spindles. Trymon had oiled the lock, but the oil had been soaked up by the rust and dust of years, and the only way for a wizard to move something by magic, unless he can harness some external movement, is to use the leverage of his mind itself.
Rincewind was trying very hard to prevent his brain being pushed out of his ears.
The lock rattled. Metal rods flexed in pitted groves, gave in, pushed levers.
Levers clicked, notches engaged. There was a long drawn-out grinding noise that left Rincewind on his knees.
The door swung open on pained hinges. The wizards sidled out cautiously.
Twoflower and Bethan helped Rincewind to his feet. He stood grey-faced and swaying.
'Not bad,' said one of the wizards, looking closely at the lock. 'A little slow, perhaps.'
'Never mind that!' snapped Jiglad Wert. 'Did you three see anyone on the way down here?'
'No,' said Twoflower.
'Someone has stolen the Octavo.'
Rincewind's head jerked up. His eyes focussed.
'Who?'
'Trymon —'
Yeah,' said Rincewind, picking up a knife and testing its blade thoughtfully. 'Luters, I expect.'
He thrust the blade into the wall, twisted it, and stepped ack as a heavy stone fell out. He looked up, counting under his breath, and levered another stone from its socket.
'How did you do that?' said Twoflower.
'Just give me a leg up, will you?' said Rincewind. A moment later, his feet wedged into the holes he had created, he was making further steps halfway up the wall.
'It's been like this for centuries,' his voice floated down. 'Some of the stones haven't got any mOrtar. Secret entrance, see? Watch out below.'
Another stone cracked into the cobbles.
'Students made it long ago,' said Rincewind. 'Handy way in and out after lights out.'
'Ah,' said Twoflower, 'I understand. Over the wall and out to brightly-lit tavernas to drink and sing and recite poetry, yes?'
'Nearly right except for the singing and the poetry, yes,' said Rincewind. 'A couple of these spikes should be loose—' There was a clang.
'There's not much of a drop this side,' came his voice after a few seconds. 'Come on, then. If you're coming.'