He slept fitfully and was fully awake before dawn on Sunday morning. He ate a frugal breakfast and changed into workman's overalls and tennis shoes from the package before he began a cautious reconnaissance of the House. The building was utterly silent and deserted. Looking down the stairs he saw that the front doors were barred and all the lights were extinguished. He moved about with more confidence, and tried the door to the press gallery. It was unlocked and he stood at the rail and looked down into the chamber where all the laws that had enmeshed and enslaved his people had been enacted and he felt his rage like a captive animal inside his chest, clamouring to be set free.

He left the gallery and went down the staircase into the entrance lobby and approached the high main doors of the chamber. His footsteps echoed from the marble slabs. As he had expected, the doors were locked, but the locks were massive antiques. He knelt in front of them, and from his pocket took the folding wallet of locksmith's picks.

His training in Russia had been exhaustively thorough and the lock resisted him for less than a minute. He opened one leaf of the door a crack and slipped through, closing it behind him.

Now he stood in the very cathedral of apartheid, and it seemed to him that the evil of it was a palpable thing that pressed in upon him with a physical weight and shortened his breathing. He moved slowly up the aisle towards the Speaker's throne with the massive coat of arms above it, and then he turned to the left, skirting the table on which the mace and despatch boxes would lie, until he stood at the head of the government front benches, at the seat of the prime minister, Dr Hendrik Frensch Verwoerd,'and Moses' broad nostrils flared open as though he smelled the odour of the great beast.

With an effort he roused himself, setting aside his feelings and his passions, and became as objective as a workman. He examined the bench carefully, going down on his stomach to peer beneath it. Of course, he had studied every photograph of the chamber that he had been able to obtain, but these had been pathetically inadequate.

Now he ran his hands over the green leather; the padding was indented by the weight of the men who had sat upon it, and at this close range it was scuffed and cracked with wear over the years. The bench frame was of massive mahogany, and when he groped up beneath the seat he found the heavy cross members that strengthened it. There were no surprises here, and he grunted with satisfaction.

He returned to Shasa's office, letting himself in through the panel door, and went immediately to unpack the altar chest. Once again he was careful to lay out the contents so that it could be repacked in exactly the same order. Then he climbed into the chest and lifted the floor panels.

The food he set aside for his evening meal, and he piled the blocks of plastic into the blanket. One of the advantages of this explosive was that it was inert and could endure the roughest handling.

Without a detonator, it was completely safe.

He picked up the four corners of the blanket and slung it over his shoulder like a tent bag, and then hurriedly went down to the assembly chamber again. He stowed the blanket and its contents under a bench where it would escape casual discovery and. went back to the office to fetch the tool kit. The third time he descended to the chamber, he locked the main doors behind him, so as to be able to work in total security.

He could not risk the noise of using an electric drill. He lay on his back beneath the prime minister's bench and began laboriously setting the staples into the mahogany above his face, boring the holes with the hand drill and then screwing in the threaded staples. He worked meticulously, pausing to measure and mark each hole, so it was almost an hour before he was ready to start placing the blocks of plastic. He arranged them in stacks of five, ten pounds of plastic in each stack, and wired them together. Then he wriggled back under the bench and secured each stack of five blocks in place. He threaded each tag end of wire through the loop of a separate staple and twisted them up tightly, then he reached for the next stack of bricks and set that in neatly against the last until the entire underside of the bench was lined with explosive.

Then he crawled out and checked his progress. There was a lip of mahogany below the leather cushion which completely hid the layer of blocks. Even when he squatted down as a person might do to retrieve a pen or fallen order paper from under the bench, he could not see a trace of his handiwork.

'That will do,' he murmured, and started to clean up. Meticulously he brushed up every speck of sawdust from the drilling and the offcuts of wire, then he gathered his tools.

'Now we can test the transmitter,' he told himself and hurried upstairs to Shasa's office.

He inserted the new torch batteries in the transmitter and checked it. The test globe lit up brightly. He switched it off. Next he took the radio detonator from its cardboard box and placed the hearing-aid battery in its compartment. The detonator was the size of a matchbox, made of black bakelite with a small toggle switch at one end. The switch had three positions: 'off', 'test' and 'receive'. A thin twist of wire prevented the switch accidentally being moved to 'on'.

Moses switched it to 'test' and laid it on the sofa, then he went to the transmitter and flipped the 'on' switch. Immediately the tiny globe at one end of the detonator case lit up and there was a loud buzz, like a trapped bee inside the casing. It had received the signal from the transmitter. Moses switched off the transmitter and the buzz ceased and the globe extinguished.

'Now I must check if it will transmit from here to the assembly chamber." He left thee transmitter on and descended once again to the chamber. Kneeling beside the prime minister's bench, he held the detonator in the palm of his hand and held his breath as he switched it to 'test'.

Nothing happened. He tried it three times more, but it would not receive the signal from the office upstairs. Clearly there was too much brick and reinforced concrete between the two pieces of equipment.

'It was going too easily,' he told himself ruefully. 'There had to be a snag somewhere,' and he sighed as he took the roll of wire from the tool kit. He had wanted to avoid stringing wire from the chamber to the office on the second floor; even though the wire was gossamer thin and the insulating cover was a matt brown, it would infinitely increase the risk of discovery.

'Nothing else for it,' he consoled himselfi He had already studied the electrical wiring plan of the building that Tara had procured from the public works department, but he unrolled it and spread it on the bench beside him to refresh his memory as he worked.

There was a wall plug in the panelling behind the back benches of the government section. From the plan he saw that the conduit was laid behind the panelling and went up the wall into the roof. The diagram also showed the main fuse box in the janitor's office opposite the front door. The office was locked but he picked the lock without difficulty and threw the main switch.

Then he returned to the chamber, located the wall plug and removed the cover, exposing the wiring, and was relieved to find that it was colour-coded. That would make the job a lot easier.

So he left the chamber and went up to the second floor. There was a cleaner's cupboard in the men's toilet that contained a step-.

ladder. The trap door that gave access to the roof was also in the men's toilet. He found it and set the step-ladder below it. From the top of the ladder he removed the trap door and wriggled up through the square opening.

The space below the roof and the ceiling was dark and smelled of rats. He switched on his Penlite and began to pick his way through the forest of timber joists and roof posts. The dust had been undisturbed for years and rose in a languid cloud around his feel He sneezed and covered his mouth and nose with a handkerchief a he went forward carefully, stepping from beam to beam, countinl each pace to keep himself orientated.