IV 



- 



PREFACE TO THE SECOND EDITION. 



In preparing a second edition of Mr. H. B. Woodward's 

 memoir on the Geology of the London District it was necessary, 

 as far as possible, to bring the information up to date and at the 

 same time to effect some condensation wherever that could be 

 done without impairing the usefulness of the book. The task 

 was entrusted to Mr. Bromehead, who has had considerable 

 experience of field work in the London District. He has been 

 assisted by Mr. Chatwin, who has revised the palaeontological 

 information. 



The Special London Map (in four sheets) is still on sale, but 

 will be superseded in a few years by the New Series one-inch 

 Sheets, of which Windsor (269) and South London (Sheet 270) 

 are already published, with descriptive memoirs. 



The relief model of the geology of London, exhibited in the 

 Museum of Practical Geology, has recently been renovated and 

 revised in accordance with the six -inch survey. It is illustrated 

 by a special collection of rocks, fossils and other specimens. 



Assistance in the preparation of this edition has been given 

 by Mr. Henry Dewey, Mr. J. A. Howe, Dr. R. L. Sherlock 

 and Mr. R. W. Pocock. 



JOHN S. FLETT, 



Director. 

 Geological Survey Office, 



28, Jermyn Street, London, S.W.I. 

 12th May, 1922. 



