PREFACE. V 



learn ;" and that, unless they are very stupid, they generally 

 do learn something new every day of their lives. 



It has been necessary, to introduce many terms of a tech- 

 nical character, but none are used which have not been de- 

 fined, or whose signification may not be discerned by a care- 

 ful examination. We trust, therefore, that the farmer will 

 not be deterred from reading the work, because he may find 

 words belonging to sciences which are unknown to him. If 

 he will not only read the book, but study it, and that too 

 in course, we venture to assure him, that he shall be able to 

 understand what is written, whether he is benefited by it 

 or not. 



In the preparation of the work, the author has consulted 

 several writers on Agricultural' Chemistry, particularly Sir H. 

 Davy, Chaptal, Sinclair, Liebig, Daubeny, Johnston and Da- 

 na ; and also, various Reports and periodical publications. 

 The view^s of each writer, on many important points, have 

 been presented, and their theories examined. 



In addition to an Index, a very full Table of Contents is add- 

 ed. This table is intended to contain a complete analysis of 

 the work, in the form of topics. The design of this table is, to 

 fiirnish the student with the most important subjects for his 

 attention ; and, should the work ever be so fortunate, as to 

 be introduced as a text-book into cur academies, these topics 

 may serve the purpose of direct questions. 



It is proper, in this place, for the author to acknowledge 

 his particular obligations to Dr. Samuel L. Dana of Lowell, 

 for the many kind suggestions which he has made from 

 time to time, and for the important aid afforded by his late 

 work ; although not received, until nearly the whole of this 

 work was prepared for the press. 



The author would also express his obligations to the Trus- 

 tees of Phillips Academy, who have so promptly responded to 

 the suggestion of preparing a text-book for the use of the In- 

 1* 



