PREFACE 



TO HTH KDiriON 



Volume has again been thoroughly revised and 

 brought up to date. Numerous alterations and additions 

 have been made in it, but without altering the simple- 

 style of arrangement and treatment which was originally 

 adopted, and which, as shown by the continued sale of 

 large impressions, appears to have been found useful by 

 beginners in Field-Geology. 



GEOLOGICAL SURVEY OFFICE, 

 LONDON, May 1900. 



