NO IDENTIFICATION.

Floyd looked slightly annoyed.

'Very well. Please give me the message.'

IT IS DANGEROUS TO REMAIN HERE. YOU MUST LEAVE WITHIN FIFTEEN DAYS.

'That is absolutely impossible. Our launch window does not open until twenty-six days from now. We do not have sufficient propellant for an earlier departure.'

I AM AWARE OF THESE FACTS. NEVERTHELESS YOU MUST LEAVE WITHIN FWFEEN DAYS.

'I cannot take this warning seriously unless I know its origin... who is speaking to me?'

I WAS DAVID BOWMAN. IT IS IMPORTANT THAT YOU BELIEVE ME. LOOK BEHIND YOU.

Heywood Floyd slowly turned in his swivel chair, away from the banked panels and switches of the computer display, towards the Velcro-covered catwalk behind.

('Watch this carefully,' said Dr Kim.

As if I needed telling, thought Poole...)

The zero-gravity environment of Discovery's observation deck was much dustier than he remembered it: he guessed that the air-filtration plant had not yet been brought on line. The parallel rays of the distant yet still brilliant Sun, streaming through the great windows, lit up a myriad of dancing motes in a classic display of Brownian movement.

And now something strange was happening to these particles of dust; some force seemed to be marshalling them, herding them away from a central point yet bringing others towards it, until they all met on the surface of a hollow sphere. That sphere, about a metre across, hovered in the air for a moment like a giant soap bubble. Then it elongated into an ellipsoid, whose surface began to pucker, to form folds and indentations. Poole was not really surprised when it started to assume the shape of a man.

He had seen such figures, blown out of glass, in museums and science exibitions. But this dusty phantom did not even approximate anatomical accuracy; it was like a crude clay figurine, or one of the primitive works of art found in the recesses of Stone Age caves. Only the head was fashioned with care; and the face, beyond all shadow of doubt, was that of Commander David Bowman.