After a week of revelation after revelation, former royal butler Paul Burrell published his book yesterday.

Nick Morrison looks at the impact of his decision to go public - and what may lie in store for the monarchy.

HERE he is opening the car door. There he is again, riding on the back of a coach, in full livery. And he's in this one, in top hat and tails at Ascot. When the Queen leafs through her photo albums, it must be hard to suppress a scowl at the face that always seems to be hovering in the background.

For 20 years, Paul Burrell was the discreet and devoted servant, the one who was only too happy to carry out the royal bidding as quickly as he could tug his forelock. But there must have been times in the last week when the Royal Family would have been quite happy to see that forelock separated from the rest of his body. As butler to Diana, Princess of Wales, during and after the most turbulent period of her marriage, he, more than just about anyone, knows the royal secrets - secrets he has now decided to spill.

In the years immediately following Diana's death, Burrell played the role of loyal retainer, one who would never divulge what he had witnessed. A year after that Paris car crash, he said what went on between him and his employer would remain hidden. "I was honoured and privileged to keep those secrets," he vowed, "which I intend to still keep."

But thoughts of his retirement seem to have got the better of those noble feelings. For a reported six-figure sum, Burrell sold the more spicy of those secrets to the Daily Mirror, with many more reserved for what is expected to become a best-selling book, published yesterday. He may have called it a "loving tribute" to the Princess, but within Buckingham Palace it is more likely to be seen as an act of treachery.

Indeed, in a statement issued by Prince William last week, also on behalf of his brother Harry, it was clear that Burrell's revelations were being greeted by mounting horror and astonishment. "We cannot believe that Paul could abuse his position in such a cold and overt betrayal," the statement ran.

But if money may have played a role in prompting Burrell to go to print, it seems he was also motivated by his treatment at the hands of the Royal Family while he faced accusations he had stolen from Diana's estate, accusations which crumbled when he was cleared at an Old Bailey trial last year. During a round of interviews yesterday to try and justify what he had done, he said he felt particularly let down by princes William and Harry, and he would bring up the issue if a meeting between them was ever arranged.

"I would like to give them a piece of my mind and ask them why they personally did not help me when I needed help at the worst point in my life. I tried desperately to contact them, but there was no response," he told one interviewer.

Coming on top of tales of life with the Wales's, this complaint of ill-treatment, of master spurning servant at the first sign of tough going, will do nothing for the royal reputation, according to Dr Martin Farr, history lecturer at Newcastle University.

"It could very easily be portrayed that had he not been deserted in the original trial, or had anyone at the Palace shown any sensitivity after the trial, then he wouldn't have written the book," says Dr Farr. "It could be put down to poor man-management, but it does add to the impression that this is a dysfunctional and uncaring family. This seems to be another example of the way in which the family doesn't seem to have normal concerns about how people are treated."

Despite helping to cement what is already a pretty much solidified view among many people, Dr Farr says Burrell's revelations say as much about our obsession with celebrity as they do about the monarchy itself. "They contradicted what many of us thought and that made them newsworthy, such as Philip being keener on Diana than we thought, and that does him credit. Charles and Camilla didn't come out of it particularly well, but wasn't anything we didn't know before. It is a good story, but I'm not sure it is constitutionally significant. The real novelty isn't so much in what was said, as in the fact that it was written at all," he says.

"What is interesting is that people probably thought two months ago that Diana was no longer a serious news story, but this shows people are still slightly obsessed, and no one has replaced her as a national symbol. It is unedifying, but it inevitable when you have got a culture obsessed with celebrity."

Prince William's offer to meet Burrell may be a little belated, but it seems to be an attempt to stop the butler disclosing more secrets. It is a possibility which is causing consternation at the Palace, for Burrell is said to be privy to the secrets of what Diana called the "crown jewels", a mahogany box which disappeared from Kensington Palace after Diana's death.

This box is said to contain a tape recording Diana made of a conversation with royal valet George Smith, in which he alleges he was raped by a trusted royal aide. Mr Smith also claims on the tape that he witnessed an incident between a member of the Royal Family and an aide, an allegation he has said would cause irreparable damage to the monarchy if it ever became public.

Burrell has always denied he knows the whereabouts of the box, and yesterday said he would not make the contents of the tape public, but also hinted that there could be more revelations to come, in what must have sounded like a threat to the royals.

According to royal historian Robert Lacey, William's offer may be the best way to stop Burrell from unburdening himself of more of his secrets, although it may ultimately prove futile.

"William is taking hold of the problem and using the personal relationship that Burrell has made such a fuss about, to push towards closure and some sort of finality," he says.

"By offering to meet up, William is aware of the risks that he is prepared to take. He has extended the hand of friendship and trusts to Burrell to respond. But I think Burrell will continue to tell Diana's secrets because he simply wants to make more money."

In Diana's final letter to Burrell, she spoke of how "the tide is changing", referring to a forthcoming event which would lead to "happier times and different homes", and Burrell tantalisingly says that "I know the future we were heading to". So what was this secret, too sensitive even for Burrell's grovel-and-tell? According to the man himself: "That's between the butler and the princess." That is, until a suitable offer comes along.