SEEDING MACHINERY 1 15 



known as the standard drill with the large wheels at the 

 end of the seed box and equipped with small press wheels, 

 and another where large press wheels were used and the 

 large wheels at the end of the seed box dispensed with, 

 which is spoken of as a low-down drill. 



151. Press-wheel attachment. In order to make their 

 machine become more universal, manufacturers have pro- 

 vided press-wheel attachments for those who wish them, 

 and they are detachable and do not interfere with the 

 use of the drill whether with or without them. It is to 

 be mentioned here that the drill has many conditions to 

 meet, and a drill which will do satisfactory work in one 

 section may not in another. Thus in a wheat territory, 

 where the ground is not plowed every year a drill 

 with great penetration is needed. In other sections 

 where the ground is carefully prepared this particular 

 feature is not so important. Press-wheel attachments are 

 a nuisance in turning, and it is out of the question to back 

 the machine. 



152. Covering chains. Chains are often provided to 

 follow after the furrow openers, and their sole purpose is 

 to insure a covering of the grain. 



Formerly the grain tube or the spouts which convey 

 the grain to the furrow opener were made of rubber, but 

 the best used at the present time are made either of steel 

 wire, or, still better, steel ribbon. 



153. Disk drills. Indications point toward the dis- 

 placement of all forms of furrow openers by the single- 

 disk opener. The single-disk will meet nearly all of the 

 many conditions to be encountered. The double-disk is 

 not much better in many respects than the shoe. The 

 single-disk has good penetration, and besides is especially 

 well adapted to cut its way through trash. Against it 

 stand two objections : One is that there is a tendency for 



