112 BRITISH HUSBANDRY. [Ch. VIII. 



their nature liable to vary. No landholder, or his agent for him, can be 

 supposed capable of arranging fixed rules with such accuracy as to meet 

 incidents so numerous, uncertain, and remote ; nor can any such plan be 

 carried properly into execution, unless it coincide with the interest as well 

 as the skill and means of the tenant. The general principle of the rota- 

 tions which are deemed most suitable to the land, may indeed be agreed 

 upon, and a watchful eye may be kept upon his proceedings ; but, if he be 

 a man of intelligence and integrity, they should be liberally construed ; for 

 the interest of both parties is the same, and if that of one be considered in 

 preference to the other, both will surely suffer. 



In the following chapter we purpose giving a cursory view of the com- 

 ponent parts of some soils, and their adaptation to various rotations, which 

 we have extracted from the works of eminent agriculturists, as being, in 

 our opinion, the most able summary of cultivation with which we are 

 acquainted ; for the plans there recommended are founded upon acute obser- 

 vation resting upon mature experience ; and, although the part which we 

 have taken from Von Thaer is calculated for the north of Germany, yet 

 neitlier the climate nor the husbandry are materially different from our 

 own : we therefore trust that it will be found to throw some additional 

 light on the obscurity in which the subject of vegetation is still shrouded. 



In doing this, however, we have omitted all further notice, than the 

 slight mention which we have already made, of the interesting experiments 

 recorded by De CandoUe and Macaire upon the excretory powers of plants ; 

 for although they seem to have ascertained that matter is exuded from the 

 roots, the nature of which varies according to the families of the vegetables 

 that produce them ; and the facts which they have stated will tend, if con- 

 firmed, to enlarge our knowledge of the principles of vegetation, and to 

 simplify the regulation of the course of cropping; yet the discussion of the 

 subject, in its present crude shape, belongs more properly to naturalists 

 than to farmers. 



Chapter VIII. 



ON SOILS AND COURSES OF CROPPING. 



' The rotation of crops, or, in other words, those species of plants and 

 modes of culture which best maintain the soil in a state of fertility, and 

 return the most abundant produce, has long been a disputed question 

 among naturalists, and probably will remain so ; for the inquiry has been 

 founded upon experiments made upon soils, and under climates and circum- 

 stances of a variable nature. We have numerous accounts of prodigious 

 returns from peculiar modes of cultivation ; but there are many reasons 

 why all trials which have been only casually made, and not followed up 

 through a series of years in the ordinary method of field-tillage, sliould be 

 received with distrust. 



First, they are generally made with a view to establish some peculiar 

 theory, or to try the effect of some novel idea, which, being a favourite 

 speculation, is pursued with all the bias of partiality, and recorded with a 

 degree of favour from which the most candid statements are rarely exempt. 



Secondly, tliey are usually conducted on a small scale, on ground pecu- 

 liarly adapted to the purpose, and attended to with a degree of care that 



