ADVANTAGES OF THE ROLLER. 61 



teen inches in diameter, and about the same length as the a- 

 bove mentioned wooden one. The summer fallow is greatly 

 improved in strong soils, because without its aid the large and 

 obdarate clods cannot be reduced ; and it appears that for ac- 

 complishing the different purposes for which rollers may be 

 necessary, those of various sizes and dimensions may be re- 

 quired. It is said that wooden rollers drawn by one horse an- 

 swer very well for grass and turnip land ; but massy stone rol- 

 lers drawn by two or three horses, are necessary on clayey 

 soils. "The expedition which takes place when rollers are 

 used, compared with the tedious and expensive progress of 

 breaking clods with malls, formerly the general custom,* suffi- 

 ciently proves the importance of these implements, though it 

 deserves to be remarked, that when rolling is bestow-^ 

 ed upon a spring sown field, harrowing it afterwards, is of 

 great advantage. By harrowing it after the clods are reduced, 

 the earth stands the effects of rain better afterwards, and does 

 not consolidate so firmly as when that process is neglected. 



"The spiky roller is much recommended by some English 

 writers for mellowing some clayey ground that is baked in clods. 

 It is also recommended to be passed over fields of wheat in the 

 spring, for the purpose of loosening the ground, and then to be 

 followed by a brush harrowing." But quere ; this must depend 

 on the peculiar condition of the soil and grain at the time. "Its 

 further use is to tear and loosen old grass bound meadows, for 

 the purpose of making the grass grow more thriftly again." 

 But had not such old grass bound meadows ought to be 

 ploughed up ? f 



The spiky roller is merely a wooden roller with iron teeth, or 

 spikr- drove into it. They are to be about seven inches long, 

 and drove three inches into the wood, and set four inches a- 

 part, in diagonal rows round the roller, the outer ends are not 

 to be sharp, but square. 



* This has an allusion to the custom in Great Britain ; Ihe farm- 

 ers in the United States have generally used in tillage no other 

 process to break the clods, but with the harrow. It is only in pla- 

 c^es where agriculture is progressing in a state of great improvement, 

 that it is believed to be necessary that the soil should be perfectly 

 and uniformly pulverized, either before or after the seed is commit- 

 ted to it. 



t See essay on improving land by breaking up old grass with 

 the plough. 



