I TAKE this opportunity of acknowledging with gratitude my great and 

 various obligations to all those who have lent me their aid in the pro- 

 duction of these volumes. Among these the first place belongs to my 

 friend Mr John W. Simpson, to whose suggestion the work owes its origin, 

 and to whose unfailing good nature and unerring judgment I have 

 frequently appealed and never in vain at critical junctures. To Mr 

 Arthur Stratton I owe a deep debt for valuable advice and criticism in 

 the revision of the work and the selection of illustrations, involving 

 much work and considerable inconvenience to himself. My thanks 

 are also due to Mr Arthur Tilley, of King's College, Cambridge, and to 

 Mr R. Phene Spiers, for various suggestions, and to the latter for the 

 loan of a number of photographs. 



I am greatly indebted to Mr Alan Potter for his admirable photo- 

 graphs, many of which were taken expressly for this work, and to Messrs 

 Lawrence Gotch and Philip Hepworth for their excellent measured 

 drawings and sketches. I also gratefully acknowledge the permission 

 to reproduce drawings by Messrs Louis Ambler, C. Farey, C. W. Pike, 

 V. O. Rees, Arthur Stratton, and G. G. Wornum ; the kind assistance 

 given me by Mr T. Honnor in photography and typewriting, and Mrs 

 Lament's invaluable help in compiling the Index and reading the proof. 

 I have also to record my indebtedness to the Council of the Royal 

 Institute of British Architects for subjects from old books and prints in 

 the Library, and to Messrs Arnott and Wilson for Fig. 402. 



Thanks are due to the French publishers who have with characteristic 

 courtesy permitted me to reproduce examples from their valuable works. 

 Details of the subjects and their sources are given in the Index to 

 Illustrations. Their names are as follows : Messieurs F. Boissonas, 

 Geneva; E. Twietmeyer, Leipzig; A. Calavas, F, Contet, Ch. Eggimann, 

 Ch. Foulard, A. Guerinet, and E. Levy, all of Paris. 



I can only fitly conclude this note by expressing my gratitude to rny 

 Publishers for their kindness and valuable help in many ways throughout 

 the long preparation of the book, and in particular to Mr Harry Batsford 

 for his laborious work in connection with the illustrations and printing. 



W. H. W. 



