“The usual relic chamber set in the foundations was empty, obviously robbed of its contents centuries ago. But the students had tools of which the old-time treasure-hunters never dreamed; their neutrino survey disclosed a second relic chamber, much deeper. The upper one was only a decoy, and it had served its purpose well. The lower chamber still held the burden of love and hate it had carried down the centuries – to its resting-place today, in the Ranapura Museum.”

Morgan had always considered himself, with justification, reasonably hard-headed and unsentimental, not prone to gusts of emotion. Yet now, to his considerable embarrassment -he hoped that his companions wouldn't notice – he felt his eyes brim with sudden tears. How ridiculous, he told himself angrily, that some saccharine music and a maudlin narration could have such an impact on a sensible man! He would never have believed that the sight of a child's toy could have set him weeping.

And then he knew, in a sudden lightning flash of memory that brought back a moment more than forty years in the past, why he had been so deeply moved. He saw again his beloved kite, dipping and weaving above the Sydney park where he had spent much of his childhood. He could feel the warmth of the sun, the gentle wind on his bare back – the treacherous wind that suddenly failed, so that the kite plunged earthwards. It became snagged in the branches of the giant oak that was supposed to be older than the country itself and, foolishly, he had tugged at the string, trying to pull it free. It was his first lesson in the strength of materials, and one that he was never to forget.

The string had broken, just at the point of capture, and the kite had rolled crazily away into the summer sky, slowly losing altitude. He had rushed down to the water's edge, hoping that it would fall on land; but the wind would not listen to the prayers of a little boy.

For a long time he had stood weeping as he watched the shattered fragments, like some dismasted sailboat, drift across the great harbour and out towards the open sea, until they were lost from sight. That had been the first of those trivial tragedies that shape a man's childhood, whether he remembers them or not.

Yet what Morgan had lost then was only an inanimate toy; his tears were of frustration rather than grief. Prince Kalidasa had much deeper cause for anguish. Inside the little golden cart, which still looked as if it had come straight from the craftsman's workshop, was a bundle of tiny white bones.

Morgan missed some of the history that followed; when he had cleared his eyes a dozen years had passed, a complex family quarrel was in progress, and he was not quite sure who was murdering whom. After the armies had ceased to clash and the last dagger had fallen, Crown Prince Malgara and the Queen Mother had fled to India, and Kalidasa had seized the throne, imprisoning his father in the process.

That the usurper had refrained from executing Paravana was not due to any filial devotion but to his belief that the old king still possessed some secret treasure, which he was saving for Malgara. As long as Kalidasa believed this, Paravana knew that he was safe; but at last he grew tired of the deception.

“I will show you my real wealth,” he told his son. “Give me a chariot, and I will take you to it.”

But on his last journey, unlike little Hanuman, Paravana rode in a decrepit ox-cart. The Chronicles record that it had a damaged wheel which squeaked all the way – the sort of detail that must be true, because no historian would have bothered to invent it.

To Kalidasa's surprise, his father ordered the cart to carry him to the great artificial lake that irrigated the central kingdom, the completion of which had occupied most of his reign. He walked along the edge of the huge bund and gazed at his own statue, twice life-size, that looked out across the waters.

“Farewell, old friend,” he said, addressing the towering stone figure which symbolised his lost power and glory, and which held forever in its hands the stone map of this inland sea. “Protect my heritage.”

Then, closely watched by Kalidasa and his guards, he descended the spillway steps, not pausing even at the edge of the lake. When he was waist deep he scooped up the water and threw it over his head, then turned towards Kalidasa with pride and triumph.

“Here, my son,” he cried, waving towards the leagues of pure, life-giving water, “here – here is all my wealth!”

“Kill him!” screamed Kalidasa, mad with rage and disappointment.

And the soldiers obeyed.

So Kalidasa became the master of Taprobane, but at a price that few men would be willing to pay. For, as the Chronicles recorded, always he lived “in fear of the next world, and of his brother”. Sooner or later, Malgara would return to seek his rightful throne.

For a few years, like the long line of kings before him, Kalidasa held court in Ranapura. Then, for reasons about which history is silent, he abandoned the royal capital for the isolated rock monolith of Yakkagala, forty kilometres away in the jungle. There were some who argued that he sought an impregnable fortress, safe from the vengeance of his brother. Yet in the end he spurned its protection – and, if it was merely a citadel, why was Yakkagala surrounded by immense pleasure gardens whose construction must have demanded as much labour as the walls and moat themselves? Above all, why the frescoes?

As the narrator posed this question, the entire western face of the rock materialised out of the darkness – not as it was now, but as it must have been two thousand years ago. A band starting a hundred metres from the ground, and running the full width of the rock, had been smoothed and covered with plaster, upon which were portrayed scores of beautiful women – life-size, from the waist upwards. Some were in profile, others full-face, and all followed the same basic pattern.

Ochre-skinned, voluptuously bosomed, they were clad either in jewels alone, or in the most transparent of upper garments. Some wore towering and elaborate head-dresses – others, apparently, crowns. Many carried bowls of flowers, or held single blossoms nipped delicately between thumb and forefinger. Though about half were darker-skinned than their companions, and appeared to be hand-maidens, they were no less elaborately coifed and bejeweled.

“Once, there were more than two hundred figures. But the rains and winds of centuries have destroyed all except twenty, which were protected by an over-hanging ledge of rock…”

The image zoomed forward; one by one the last survivors of Kalidasa's dream came floating out of the darkness, to the hackneyed yet singularly appropriate music of Anitra's Dance. Defaced though they were by weather, decay and even vandals, they had lost none of their beauty down the ages. The colours were still fresh, unfaded by the light of more than half a million westering suns. Goddesses or women, they had kept alive the legend of the Rock.

“No one knows who they were, what they represented, and why they were created with such labour, in so inaccessible a spot. The favourite theory is that they were celestial beings, and that all Kalidasa's efforts here were devoted to creating a heaven on earth, with its attendant goddesses. Perhaps he believed himself a God-King, as the Pharaohs of Egypt had done; perhaps that is why he borrowed from them the image of the Sphinx, guarding the entrance to his palace.”

Now the scene shifted to a distant view of the Rock, seen reflected in the small lake at its base. The water trembled, the outlines of Yakkagala wavered and dissolved. When they had reformed, the Rock was crowned by walls and battlements and spires, clinging to its entire upper surface. It was impossible to see them clearly; they remained tantalisingly out of focus, like the images in a dream.