UBHARY 



PREFACE 



The British Society for the Diffusion of Useful 

 Knowledge, was established about the year 1825, for 

 the purpose of furnishing a series of books in various 

 branches of science, better adapted to the wants of the 

 public than the old treatises, or the compilations by 

 authors but little acquainted with the subjects which 

 they endeavored to discuss. 



The Society published a series of maps, and various 

 treatises upon Natural Philosophy, History, Mathema- 

 tics, and other subjects. To these treatises the general 

 title of Library of Useful Knowledge was given, and 

 in the course of their publication it was found expedient 

 to issue works of a different character, especially adapted 

 to the agricultural interests, and to this portion of the 

 " Library" the title of '^ The Farmer's Series" was given. 

 Among the works in this department were published 

 Youatt's works on the Horse — Cattle — Sheep — and the 

 Dog; treatises on British Husbandry^ Flemish Hus- 

 handry, and the present treatise on Manures, all of 

 which acquired a wide-spread reputation. 



The subject to which this volume is devoted is an 

 (3) 



umzim 



