The production of any book involves far more than its writing. It entails much tedious and painstaking work, and I wish to take this opportunity to thank those several persons who, directly or in directly, and in numerous ways, have helped with the preparation of Structural Landforms. Many colleagues and friends have kindly supplied photographs, many of which, for reasons of space, have not been utilised. Only one request for illustrative material was directly refused, and, whether the prints supplied were used or not, I wish to thank those who went to so much trouble on my behalf. I am grateful to the many organisations and individuals who kindly gave permission to use photographs and illustrations, and whose assistance is acknow ledged in the text. Janet Saies and Janeen Nicol read the first draft, justifying their interest with the modest claim that if they could understand the text then anyone could. They could not follow all of it, and I am grateful to them for drawing my attention to ambiguous and con fused passages, for their expenditure of time, and their humour and enthusiasm. Tim Hopwood has drawn my attention to certain anachronisms in my use of structural terms, and George Sved has, over the years, done much to disembarrass my mind of some, though I fear not all, mechanically unsound ideas. Yngvar Isaacson and Bruce Curtis have generously made available their expert knowledge of certain North American areas, and I have profited greatly from discussion of particular problems in structural geomor phology with Jim Talbot, Edwin Hills, Rudi Horwitz, Armin Öpik, and Heli Wopfner. The onerous task of translating my rough sketches into line draw ings fell to John Heyward, of the Department of Human Geography, Institute of Advanced Studies, Australian National University. Apart from the field sketches, he is responsible for all the figures, and the skill and flair he has brought to his task are obvious to all. ix X Acknowledgments To John and to his superiors, who so generously and understand ing^ allowed me the use of his services, I am most grateful. My wife, Kate, quite apart from encouraging me to continue with the writing of the book in the face of more than usually difficult and trying circumstances, with her customary skill, patience and instinct, deciphered my scrawl, unravelled my amendments, and from it all produced a typescript. I am the more appreciative of her help because I know how difficult it was for her to fit in the typing between running a household, caring for a family, and sundry other good works. Most of all, however, I must express my gratitude to the General Editor of this series, J. N. Jennings. Joe has for many years now given me much help and good advice, but never so much as in the preparation of this book. For providing the opportunity to par ticipate in the series, for his liaison work between author and draftsman, for his tact, patience, encouragement, and understanding, for his many helpful suggestions, and, most of all, for his scholarly and critical mind, I thank him.