I’d like to thank Diana Owen of the National Trust, for showing me parts of Petworth House normally closed to the public, and for her insights into life there in the nineteenth century; Philip and Pat Trower and Gavin and Venetia Young for their hospitality; Pat Hunt and Kate Armitage at Otley Museum for their assiduous research on my behalf; Mark Pomeroy, Archivist at the Royal Academy, for his advice; and Professor Harold Livermore for generously opening his house, Sandycombe Lodge, to visitors. I’m grateful to Dominic Power, Andrew Hilton and Peter Lord, all of whom discussed the book with me in its early stages and made helpful suggestions. And I owe a special debt to Nicholas Alfrey, of the University of Nottingham Department of Art History, who gave me the benefit not only of his immense knowledge of Turner and of his literary acumen, but also of his friendship – listening patiently as I tried to find my way through the complexities of Turner’s art and life, reading various versions of the text, and making incisive – and always encouraging – comments.
I am extraordinarily lucky in having both an exceptional editor, Jon Riley, who guided me with his usual flawless judgement and attention to detail through the writing and revision process, and an outstanding agent, Derek Johns, without whose perspicacity and unflagging encouragement The Dark Clue would never have been conceived, let alone written.
I also want to acknowledge the help of my family, who all, in different ways, made an enormous contribution to the book – Paula by her inspiration and support; Tom, by taking an informed interest that went far beyond the call of duty; Kit, by gamely tolerating my eccentric hours and preoccupations; and my mother, by putting at my disposal her encycolpaedic knowledge of social history, and working indefatigably as a researcher (so saving me at least six month’s work), critic and morale-booster.
And finally, of course – my thanks to Wilkie Collins and J. M. W. Turner.