IRRIGATION AND DRAINING. 87 



should be sought, at the highest point where the ground 

 appears moistened, and led away to a ravine or rivulet, by a 

 drain, sufficiently deep to prevent the escape of any of the 

 water into the adjacent soil ; unless, as it sometimes happens, 

 the position and quality of water are suited to irrigation, 

 when it may be conducted over the field for that purpose. 



Swamps and Peat beds occur frequently in a hilly country. 

 These are low, level, wet lands, whose constant saturation 

 with water, prevents their cultivation with any useful plants. 

 The first object in effecting their improvement, is to find an 

 outlet for the escape of the water, to a depth of three to five 

 feet below the, general surface, according to the area to be re- 

 claimed ; the greatest depth above specified, being frequently 

 necessary to the effectual drainage, at all times, of an extend- 

 ed field. If the water in the swamp has its origin in numer- 

 ous springs from the adjoining hills, a ditch should be dug 

 around the entire outer edge, where it meets the ascending 

 land. If the water be derived from a rivulet, a broad ditch 

 should be made as direct as possible from the entrance to its 

 outlet, and deep enough to lead off all the water. If this 

 is found insufficient, additional ones may be made wherever 

 required. 



CHAPTER V. 



MECHANICAL DIVISION OF SOILS. 



SPADING. 



AFTER selecting a proper soil and placing it in a proper 

 condition, by manuring, draining, &c., the next most import- 

 ant consideration is, the further preparation of the land for 

 the reception of the seed. In small patches of highly-culti- 

 vated land, spading is resorted to, for breaking up and pul- 

 verizing the ground more effectually than can be done with 

 the plow. This is the case with many of the market 

 gardens, in the neighborhood of our large cities, and with 

 large portions of Holland, Flanders and other countries of 

 Europe. It is even contended by many intelligent and 



