In the past, in every society, elites knew how to predict them and used the knowledge to affect intimacy with celestial bodies. Sages who understood the gyrations of the moon had an advantage over the ignorant: they could claim to be privy to the plans of heaven.
Nearly 4,000 years ago, when Chinese astronomers failed to predict an eclipse, the monarch sent an army to reprimand them. Ulysses - who always used guile to keep ahead of his enemies - took advantage of the darkness to kill his wife's lovers. Amos, the prophet, used an imminent eclipse to threaten Jeroboam, King of Israel, with divine displeasure over his indifference to the poor. The Romans used another to demoralise their Macedonian enemies. Meanwhile, Athenian commanders, unable to convince their men that a blackened sun was a routine event, succumbed to defeat by Syracuse. Among the ancient Maya, kings used eclipses to reinforce their authority by staging acts of communion with the gods: they drew sacrificial blood from their sexual organs with cactus thorns, or from their queens' tongues with spiked thongs. Blood-loss induced visions in which divine messages - confirming royal policies - were received.
In the seventh century, when Sisebut became King of the Visigoths, knowledge of eclipses was one of the signs of his superiority. He wrote a poem describing how they worked and ridiculed the vulgar ignorance that ascribed them to "a heavenly hag jiggling a mirror". In the 17th century, when the first Jesuit missionaries reached China, they got privileged access to the emperor by attaining unprecedented accuracy in the prediction of eclipses. The whole practice of astronomy at court, on which the success of imperial enterprises and the life of the empire were believed to depend, was handed over to the foreigners.
Anecdotes about successful predictions have enshrined myths of progress and white supremacy. Marooned on Jamaica in 1503, Columbus tricked the natives into submission by foretelling an eclipse: his own arithmetic was untrustworthy, but he happened to have a printed almanac with him.
The same trick became a common resource of adventure-story heroes. Tintin used it to escape the stake in South America. Alan Quartermaine tried it out on the guardians of King Solomon's Mines. A recent novel of Charles Palliser's ascribes a similar attempt to King Alfred in battle against the Danes. By the same method, Mark Twain's Connecticut Yankee demonstrated his superiority over the medieval world to which time-travel took him. In the literature of colonialism, eclipse-prediction is one of the means by which the intrusive guest asserts mastery over the host-culture. In all these cases, and others like them, the modern man, the "civilised" man of superior sagacity, manipulates to his advantage the superstitious simplicity of his victims.
All such stories are deeply unconvincing. Modern people are more ignorant of the heavens than any genuine "primitives", whose nightly reading-matter is the sky. In just about every early civilisation we know of, astronomy was a revered art, and astronomical record-keeping was one of the main uses of numeracy. Long before writing was invented - scores of thousands of years earlier, according to some scholars - men kept tally-sticks notched with observations of the motions of the moon. Regularities as obvious as eclipses are unlikely to have eluded most elites once long-term records were available.
Nowadays, no elite can control the relevant information. The arithmetic of eclipse-prediction, though tedious, is accessible to all. No one can make a mystery out of it; but some people can make money. Legends of the eclipse of 1999 will be handed down, like those of the past, with a sub-text about manipulation of the gullible. This time, however, it is money that changes hands, not authority.
In exploiting a brief thrill in the dark, the eclipse industry comes second only to prostitution. Eclipses happen all the time all over the solar system. The fact that this one will be visible - weather permitting - in the holiday season in a densely populated part of the world makes it special in only one respect: commercially, it's highly exploitable.
Cornwall mismanaged the opportunity and had to sell bookings off cheaply in the past few days. But other places in the path of the eclipse expect big profits. Romania has its own Official Solar Eclipse Website, designed to lure tourists into the shadow of the moon in Dracula country. Some people are contriving to spend as long as possible in darkness by following the shadow at sea. A competition winner will join high-rolling pundits in Concorde, tracking the eclipse from Nova Scotia to Bengal.
This is the first August in recent history when European holiday-makers have rushed to elude the sun. Among trash eclipse-experiences on offer are a "blues festival with stones and druids", a themed "moon goddess" night at a disco near where I live, and a seminar in Tennessee on the effects on communications with extra-terrestrials.
The solar eclipse has inspired lunatic spending. Astrologers have never had so many clients. The eclipse is like the millennium and the moon landing - a moment of utter insignificance, combined with apparently universal interest. It's the ultimate fix for the age of the transient: the sun's and the moon's 15 seconds of fame. Never mind if you miss the eclipse: what matters is to have paid to see it. According to the health-police, you are better off watching it on television and celebrating the triumph of virtuality over reality: the heavens perform an act of striptease before our eyes, and we have to watch furtively, through our peep-show technology.
If you do get away from the screen and out under the sky, never mind if clouds are thick or neurosis about eye-damage makes you blink at the critical moment. Never mind if the whole thing only lasts a few seconds. Compared with all others, this eclipse will be artificially prolonged and, on television, tediously repeated. You can protract the moment by practising beforehand with your cardboard (or deluxe plastic) eclipse- viewer. Afterwards, you can wear the T-shirt. If you are one of the lucky entrepreneurs or pundits who can make money out of e-day, you can spend many happy hours of recollection totting up. People will watch it with no real hope of seeing very much. The big question is, what do they see in it? What emotions are being touched, what meaning symbolised, what hopes and fears aroused?
In part, herd instinct accounts for the popularity of eclipse-watching. It's like being in Trafalgar Square on New Year's Eve, or in the queue for the Hard Rock Cafe? or Madame Tussaud's. Nothing much happens and the climax - such as it is - is hardly worth the trouble. But folk congregate just to be part of the buzz of the crowd.
Noble motives jostle instinct. Some eclipse-groupies want to experience a moment of awe - a conviction that there are forces in nature beyond our reach, uncorruptible by our power to pollute. Some want a taste of the power associated with mastery of eclipses in historical and literary tradition. Some have a magical attitude to the event and expect mutations in their own lives. Others want to recreate a primitive experience - to feel a tingle of fear at chill and darkness, cosmically ordained. Some want to play kudos-games. "Where did you go for the eclipse? Oh, what a shame! We had a wonderful mountain-top in Transylvania." Afterwards, when you hear them talk about the awe, that hollow sound in the background will be the clink of coins in promoters' coffers.
Felipe Fernandez-Armesto's `Truth: A History' is published by Black Swan at pounds 6.99