The Doctor and Professor Jaeger were hard at work.  It wasn't a happy collaboration.  Jaeger resented having to give time to the Doctor's concerns.  His resentment was worsened by the high-handed way in which the Doctor had appropriated several of his valuable pieces of equipment, cannibalising them and linking them together in an incredibly complicated electronic lash-up, its purpose, if it had one, defeating Jaeger completely.  Reduced to the status of a lab assistant, he sulkily linked circuits and tested connections under the Doctor's direction.

The Doctor seemed to be in a sunny mood, chatting idly as he worked.  'Can't think why you people ever came to Solos in the first place.'

Jaeger grunted.  'Thaesium, Doctor.  Solos is one of the richest fuel sources in the galaxy.  Or rather it used to be.  The deposits are exhausted now.'

'So you plan to colonise the planet in earnest - if you can change the atmosphere?'

Jaeger frowned suspiciously.  'That's my concern, Doctor, not yours.'

'The Solonians, too.  It's their planet.'

'It was their planet.  Doctor - you did say Doctor, didn't you?'

The Doctor checked the circuit Jaeger was working on, found the connection was faulty, moved Jaeger aside and finished the job himself.  'There, that's better,' he said reprovingly.  'We'll need that to hold the Proton beam steady - Professor.'

Jaeger said sourly, 'This whole thing's a waste of time.  No one's ever achieved particle reversal - it's still only theory...'

The Doctor made a few final adjustments and stepped back, studying his creation with satisfaction.  The final effect was rather like a giant microscope.  'On the contrary, old chap,  I find it a very useful research technique.'  He took the box and put it on a small raised platform in the centre of the apparatus.

Jaeger looked scornfully at the ramshackle assemblage of equipment.'  And what do you hope to achieve by all this?'

'I expect the particles to reverse,' explained the Doctor patiently.  'What is outside will be on the inside, and what is inside will be on the outside - where we can see it! '

'Rubbish!'

The Doctor grinned.  'You'd better come over here and see for yourself.'  He moved to the on/off switch, which he had prudently rigged up at some distance from the apparatus.  The Doctor threw the switch and, to Jaeger's astonishment, he saw the box glow, shimmer, and dissolve into a pile of ancient-looking scrolls and dusty parchments.  There was a bang, a flash, and a puff of smoke.  One of the circuits blew and the box was a box again.

The Doctor sighed and moved over to the apparatus.  Gingerly he touched the blackened circuit.  'Ah well, always a snag or two at first!'

'But it worked,' said Jaeger incredulously.

'Well of course it worked.  Did you see what was inside?'

'I got a glimpse of some kind of ancient documents...  But the process, Doctor.  It actually worked.'

The Doctor nodded.  'All over in a flash, you might say!'

They were interrupted by the Marshal.  He marched into the laboratory, Stubbs at his heels, and glared round suspiciously.  'Have you seen any sign of Varan?'

The Doctor looked blankly at him. 'Have I seen who?'