24 . BULLETIN 592, IT. S. DEPARTMENT OF AGRICULTURE. 
Exercise 5. — Assembling Mowing Machine and Hay Rake. 
See Farmers' Bulletin 638, Exercise 27, Assembling a Machine. 
Exercise 6. — Study of Self Binder. 
Lesson 11. — Potato and Root Diggers. 
1. Potato diggers. 
2. Root diggers. 
Lesson 12. — -T7irasTiing Machines. 
1. The grain separator. 
2. Special thrashing machines. 
3. The cotton gin. 
Lesson 13. — Machines for Preparing Stock Food and Seeds. 
1. Feed mills, grinders and corn shellers. 
2. Ensilage and root cutters. 
3. Fanning mills. 
Exercise 7. Study and Use of Feed and Fanning Mills. 
This exercise may be carried on most profitably on a neighboring 
farm or at a feed store. 
Lesson 14. — Farm Conveyances. 
1. Wagons and trucks. 
2. Lighter vehicles. 
Lesson 15. — Spraying Machinery. 
1. Hand sprayers. 
2. Power sprayers. 
Exercise 8. — A Study of Spraying Machinery. 
Lesson 16. — Power on the Farm. 
1. Elementary principles and definitions. 
2. Measurement of power. 
3. Transmission of power. 
Lesson 17. —Animals as a Source of Power. 
1. The horse, mule, and the ox. 
2. Use of the treadmill. 
Exercise 9. — Fitting Collars to Horses or Mules. 
See Farmers' Bulletin 638, Exercise 6, Fitting Collars on Horses. 
Exercise 10. — Hitching Three or More Horses or Mules. 
See Farmers' Bulletin 638, Exercise 7, Hitching Up One to Four 
Horses. 
Exercise 11. — Repairing Harness. 
See Farmers' Bulletin 638, Exercise 9, Repair of Harness. 
Lesson 18. — Wind as a Source of Power. 
1. Possibilities. 
2. Windmills. 
Special reference. — Use of Windmills in Irrigation in the Semiarid West, Farmers* 
Bulletin 394. 
