Not even the Kings and Queens of England are allowed to rest in peace in their tombs in the abbey: over the past 20 years, visitors have either taken or damaged beyond repair the crowns of Henry V and coronets of the Countesses of Suffolk and Sussex, and removed bits of mosaic from Edward the Confessor's shrine. Time and time again, one of Wordsworth's fingers is broken off after being replaced. Most recently, part of a brass candle-bracket was pulled off the monument to the 14th-century Countess of Pembroke.
In the late Eighties, a gilded wooden crown was placed on the 16th-century tomb effigy of Elizabeth I to replace the original, lost in the last century. Only weeks later, someone walked off with it, after pulling it through a protective iron grille.
'It was a beautiful gilded wood crown, but not the solid gold they must have thought it was,' said an abbey spokeswoman. The abbey learned its lesson: a metal replica was bolted to the head.
Jane Fawcett, an architectural historian who has researched the abbey's problems for a book on tourist damage to ecclesiastical sites, said that the Queen's original collar has also disappeared.
In the nave north aisle, the monument to Countess Beaufoy by Grinling Gibbons, the 17th-century master carver, has only three fingers on one hand. A regular target is a monument to a Major Andre, who was hanged for treason in the American War of Independence. Since then he has also lost his head - several times: it has been taken from a relief carving. That of George Washington, on the same carving, has also been removed more than once.
Mrs Fawcett said: 'Over the past few years the west towers have been restored at a cost of some pounds 22m, and the restoration of the exterior of the Henry VII Chapel has just begun. However, the problems inside remain to be solved.' She believes that the abbey has 'an inadequate number of staff to deal with the enormous influx of visitors'.
It is that enormous influx that is the problem Donald Buttress, the surveyor of the fabric, said that, although staff patrol the abbey, 'they've got to go to the lavatory some time, and backs are sometimes turned. . . . People pick at monuments and details repeatedly go.'
Mr Buttress added: 'The damage in monetary terms is small . . . it's not so much the money as the irritation. Fingers have to be modelled and plaster cast. A comparable marble has to be found; also, a way of fixing it. It can take three or four months.'
However, Mrs Fawcett said that the damage was serious: 'Historical evidence is being lost.'
Some damage to the Abbey is entirely unintentional. Mr Buttress said: 'The greatest problem is the enormous wear and tear.' The floor is suffering most - seven million feet walk on it each year. 'The only way to prevent further damage is to introduce slippers or close the place,' said Mr Buttress.
The Abbey spokeswoman said that, although some monuments are protected by railings, there was not enough space to put them around others - 'and aesthetically, we would not want to'. The authorities are considering doormats that remove abrasive grit from shoes and 'traffic management' schemes, although railings and ropes tend to cause congestion.
There is nothing new about people stealing a souvenir or two. The silver plating from Henry V's effigy disappeared in the 16th century. But modern times offer a drastic solution. The heraldic crest on one monument seems to attract particular attention. It is shaped like a porcupine made from a block of stone with wooden quills. 'They go all the time,' Mr Buttress said. 'Perhaps we should connect them to the mains and give people an electric shock as they pull them out.'