EDMUND RUPFIN, EDITOR AND PROPRIETOR. 



ELEMENTS 



AGRICULTURAL CHEMISTRY : 



BY SIR HUMPHRY DAVY, Baht. LL. D., F. R. S. &c. 



PREFACE 



TO THE FIRST AMERICAN FROM THE FIFTH 

 AND LAST ENGLISH EUITION. 



The text of the last English edition of Davy's Ele- 

 ments of Agricultural Chemistry, is precisely the 

 same witii that of 1827, which received the latest al- 

 terations and improvements made by its illustrious au- 

 thor. But besides that entire text, this, which will be 

 an exact reprint ot the last London edition, has the 

 notes tlien appended by the pen of the author's brother, 

 and co-laborer in chemical investigation, Dr. John 

 Davy. 



No American edition of this valuable work has been 

 published from any later than the first English; and 

 even of those early and imperfect editions, few if any 

 copies can now be found for sale. The work, in book- 

 sellers' phrase, has long been "out of print;" and there 

 are very few works that so well deserve to be reprint- 

 ed, or are more essential to the library of every intel- 

 ligent agriculturist. 



It has therefore been thought that it would be an 

 acceptable and important service to the readers of the 

 Farmers' Register, to furnish them with the last edition 

 of this valuable work, in so cheap a form as the pages 

 of this journal will afibrd. — Ed. Far. Reg. 



ADVERTISEMENT TO THE FIFTH EDITION. 



In this edition, the text of the last, to which the 

 advertisement of the author prefixed refers, has 

 been scrupulously preserved unaltered. The only 

 liberty I have taken has been in adding a few foot 

 notes, at the request of the publishers, chiefly re- 

 lating 10 facta ascertained since 1826. 



John Davy. 



Fort Pitt, Chatham, Nov. 5, 1835. 



ADVERTISEMENT TO THE FOURTH EDI- 

 TION. 



During ten years, from 1802 to 1812, I had the 

 honor, every session, of delivering courses of lec- 

 tures before the Board of Agriculture. I endeavor- 

 ed, at all tinnes, to follow in them the progress of 

 Vol. VI.— 73 



discovery; they fiierelbre varied every year; and 

 since they were first published in 1813, some con- 

 siderable improvements have been made in chemi- 

 cal science, which have rendered many alterations 

 and additions necessary. 



I am indebted for much useful information to 

 many jrentlemen who have endeavored to improve 

 asriculture, and to apply scientific principles to 

 ihis most important of the arts; of which acknow- 

 ledgments will be found in the body of the work. 

 I hope there are no omissions on this head; but 

 should they exist, I trust they will be attributed to 

 defect of recollection, and not to any want of can- 

 dor or of gratitude. 



Where 1 have derived any specific etatementa 

 from books, I have always quoted them; but I 

 have not always made reftjrences to such doc- 

 trines as are become current, the authors of which 

 are well known; and which may be almost con- 

 sidered as the property of all enlightened minds. 

 In revising this work for the fourth edition, I 

 have been Ibrcibly struck with its imperfections, 

 and I regret that I have been able to do so little to 

 render it more worthy of the approbation of those 

 readers lor whom it was designed. My object 

 has been principally to dwell upon practical princi- 

 ples, and practical applications of science; and it is 

 in the farm, and not in the laboratory, that these 

 can be put to the test of experiment; and my du- 

 ties and pursuits have rendered it impossible for 

 me to do more than point out the path of inquiry — 

 to indicate the road to improvement. The man- 

 ner in which the work has been received, both in 

 this country and the continent, induces me to hope 

 that its object, however humble, has been to a cer- 

 tain extent attained, and that it has not been with- 

 out its utility, 



I have retained an appendix containing an ac- 

 count of the experiments on grasses instituted by 

 the Duke of Bedford at VVoburn, because many of 

 these experiments are alluded to in the body of the 

 work. I am happy, however, to be able to refer 

 my readers to a much fuller and more detailed ac- 

 count of this subject of investigation, in a treatise 

 published by Mr. George Sinclair, entitled Hort. 

 Gram. JVoburnensis, and which, from the nature 

 ot the details, and the singular modesty and clear- 

 ness wiih whicji they are given, is well worthy 

 the perusal of all persons inleresied in agricultural 

 pursuits. 



H. Davy. 



Park Street, Janmry !, 1827. 



