Once I was over the shock of realising that it was over fifty years since ''The Sun King'' was published and just about as long since I first read the book, the memories came rushing back and I couldn't wait to settle down to an indulgent read. And it ''is'' indulgent: it might ''look'' like history or biography, but this is more in the nature of a gossipy conversation with someone who has seen it all, is shocked by nothing and is prepared to tell all she knows with supporting detail.