:RODUCTION. 



mediately elucidated by experiment, it is my intention to 

 advert in the present work, by way of suggesting trials in 

 the field or feeding-house, out of which we may hope to see 

 light spring up. 



To individuals anxious to enter upon such practical in- 

 vestigations and there are many such the suggestions 

 I have ventured to offer will point out what they may 

 respectively do for the advancement of scientific agricul- 

 ture. To societies, I believe, they will be no less valuable 

 in indicating what they may, by premiums and other 

 forms of encouragement, stimulate their members benefi- 

 cially to undertake. 



It is only by means of conjoined experiments in the 

 field, the feeding-house, and the laboratory all made 

 with equal care, conscientiousness, and precision that 

 scientific agriculture can hereafter be with certainty ad- 

 vanced. If we have been long in getting upon the right 

 road, we ought to advance the more heartily now we have 

 found it. 



DURHAM, August 1849. 



