TRACTION ENGINE IN DRY-FARMING 261 



moist soil. To the good dry-farmer this appeals as an ad- 

 vantage, for packing the soil closes up the air spaces in the 

 lower half of the furrow and thus prevents a loss of moisture, 

 besides leaving the ground smooth and firm to facilitate har- 

 vesting. The firm earth conducts heat more rapidly, and packed 

 subsurface soils warm up more quickly in the spring. Too 

 often this work of packing is neglected on account of the extra 

 drain on the energy of the work animals. The heavy tractor's 

 own weight and its ample power remove the difficulty. 



It is thoroughly established that the disk should precede, 

 as well as follow, the plow in dry-land agriculture. The mixture 

 of chopped stubble and loose soil thus thrown to the bottom 

 of the furrow forms a perfect union with the subsoil, in contrast 

 with the big, dry clods usually plowed under. Capillary 

 connection with the subsoil is more quickly reestablished, the 

 deep moisture rises, and decomposition of the buried vegetation 

 is hastened. Lack of time and power usually prevent the 

 practice of this valuable method. With teams, this operation 

 must be done separately, but to owners of traction engines the 

 addition of disks behind the plows is a mere detail. 



No manageable team can perform more than one operation 

 at one time. With horses seeding must wait on the work of 

 the plow, packer and disk plowing on the completion of the 

 harvest. Sun and weeds draw moisture from the unprotected 

 soil in the meantime. But the harvester may precede the 

 tractor, the disk or plow may follow, and in an instant the ground 

 passes from the shadow of the standing grain to the shelter 

 of the earth mulch. Instead of separate trips for the plow, 

 the roller, the disk and the harrow, the engine accomplishes 

 all at once. Or the plow, the packer, the disk and seeder may 

 work as one, to give the sown seed every advantage of moisture 

 and time for growth. Instead of countless footsteps, each 

 sinking deeper as the soil is made more mellow, the path of the 

 tractor is made but once. Instead of a loss of power in trav- 

 ersing the soft ground, there is a fast grip of traction wheel on 



