I have been astonished by the kindness and help that I have received in the preparation of this document. I should like to thank Mr. and Mrs Anthony Archer Wills for their inspiration and guidance during my apprenticeship and after, Paul Collingridge for his valued suggestions, The Chairman and members of the Fountain society, particularly Anne Lohman. Mr Peter Jeeves. Mr. Jonathan Minns and the staff at the British Engeneerium. And most of all Felicity-Ann whose tolerance, support and hard work has made this dissertation possible.