PREFACE 



THE contents of this volume formed the substance 

 of a course of lectures delivered by the author as 

 Sibthorpian Professor of Rural Economy in Michaelmas 

 Term, 1896. The subject of the final chapter did 

 not actually form part of these lectures, though it 

 had been prepared for delivery if time permitted. 

 The whole of the matter has since been carefully 

 revised. 



The form of lectures has not been adhered to in 

 the present volume ; the language has in fact been 

 greatly condensed. The title of lectures has, however, 

 been retained, as it best expresses the character of 

 the work. This is not a textbook, dealing exhaus- 

 tively with the physical properties of soils ; but 

 lectures, discussing with some fullness particular por- 

 tions of the subject. 



In these lectures the attempt has been made to 

 treat every subject from an experimental point of 

 view, and a considerable space will be found occupied 

 by accounts of the investigations which appear to 

 have thrown most light upon the subjects discussed. 



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