170 EUROPEAN AGRICULTURE. 



not ascertained, but, assuming a similar quantity to that found 

 in the Edinburgh sewer-water, the amount applied must have 

 been about 1792 gallons per acre, which is less than the quantity 

 which Mr. Smith proposes to apply to tillage land under his 

 improved method of conveyance. 



The proposition at first is startling, and may awaken incredu 

 lity. I can only say that the plan is proposed and approved by 

 men of as much engineering skill, and of as much practical expe 

 rience, as are to be found in the world. It certainly should not 

 be condemned, unheard, in a day when cities are every where 

 lighted with blazing air ; information is communicated hundreds, 

 and soon will be thousands, of miles, instantaneously, by means 

 of electricity; and men are conveyed from one end of a conti 

 nent to another, over wide-spreading lands, and heaving and 

 boisterous oceans, with the swiftness of a swallow s flight, under 

 the wings of a steam dragon. 



Having now treated at large some of the prominent operations 

 in English husbandry, I shall proceed to speak of other points 

 in their management, which deserve attention. 



CIV. THE ROTATION OF CROPS. 



THE rotation of crops implies the alternation or succession 

 of different crops on the same land. It is well ascertained by 

 frequent and long experience, that where the same cultivated 

 crop is frequently repeated on the same land, and allowed to per 

 fect itself, its product will be diminished, and in some cases will 

 fail altogether. The grasses would seem to present an exception 

 in this case ; but they are commonly mowed or depastured, and 

 so do not ripen their seed. Where grasses proceed to perfection, 

 certainly it may be said, in respect to many of them, that they 

 are subject to the same rule. Forest-trees likewise may be con 

 sidered as forming an exception, though it must be remembered 

 that they supply their own nutriment from the decay of their 

 own foliage, and that, although they bear fruit while young, yet 

 they are many years in reaching a perfect maturity ; and even 



