TILLAGE MACHINERY 8? 



ards and the disks and between the weight boxes and the 

 disks. Good clearance will prevent clogging in wet and 

 trashy ground. In order to secure flexibility of the gangs 

 it is almost essential to have spring pressure to keep the 

 inside ends of the gangs down. There is a natural tend- 

 ency for the gangs to raise at the center. If three horses 

 are to be used, it is advisable to have a stub tongue and 

 an offset pole. Patent three-horse eveners to remove side 

 draft with the pole set in the center are not to be advised. 

 A liberal amount of material must be used in the con- 

 struction as well as gopd workmanship for instance, a 

 heavy gang bolt with a lock nut. A square gang bolt is 

 considered better than a round one. 



125. Tongueless disk harrows are now made with a 

 truck under a stub-tongue. These harrows, no doubt, 

 make the work lighter for the team, but sacrifice a certain 

 amount of control in handling the harrow. This feature 

 is of more importance under certain conditions than 

 others. A tongue truck is also used and is a very satis- 

 factory addition to the harrow. 



126. Plow-cut disk harrows. Harrows have been con- 

 structed for several years with disks which have a raised 

 or bulging center, the idea being that the dirt in being 

 forced up over the raised center is turned over much like 

 it would be from the moldboard of a plow. It is claimed 

 by the manufacturer that this shape enables the harrow 

 to cover the small trash better, that it leaves the -ground 

 leveler, and the harrow has better penetration on account 

 of the shape of the disk blades. All these claims are de- 

 nied by other manufacturers. 



THE ROLLER AND FLANKER 



127. The land roller is a very efficient tool for working 

 up a fine tilth and for making the ground smooth and 



