At last the book is finished – and I have now been asked to put my mind to the Preface! It occurs to me that writing a Preface is a unique art form. Admittedly, after limited research into Preface-writing, I propose, like innumerable authors before me, to start with the usual whinge – yes, to paraphrase Mrs Beeton from the Preface of her famous cookbook, if we had known ‘. . . what courageous efforts were needed to be made’, I am quite sure that we would never have started this enterprise. However, it is clear that one of the.