KEKOSENP: and gasoline engines 453 



furnishes power to move these machines over the field, although 

 in some cases the power to operate the mechanism is furnished 

 by an auxiliary engine mounted on the machine. 



As already mentioned, the tractor is used to furnish power for 

 all kinds of belt work. Such operations on many farms repre- 

 sent nearly fifty per cent of the work for which the tractor will 

 be used. The increasing use of silos makes it necessary to have 

 power to operate the ensilage cutter; wherever small grain is 

 raised there is threshing to be done ; on corn belt farms there is 

 always a lot of corn to be shelled, while it is not at all infrequent 

 to find the tractor furnishing power to shred the fodder and 

 husk the ears at the same time. Baling hay and straw, pumping 

 water for irrigation, sawing wood, grinding feed, and a dozen 

 other odd jobs fall to the lot of the mechanical horse. 



While the gas tractor naturally is most satisfactory and effi- 

 cient when used on level land and on soil where a good footing is 

 obtained, it is to-day being used under nearly every farming 

 condition found in the country. Often special attachments are 

 necessary to make it satisfactory for use under such conditions 

 as soft ground, among stones, etc., but practically all these prob- 

 lems have been solved very satisfactorily. 



While the principal objection to the early tractors was their 

 heavy depreciation, the later machines have demonstrated that 

 a life at least equal to that of a horse may be expected from 

 them when they are given proper care and attention, particu- 

 larly with respect to lubrication. It is a well-known fact that 

 nearly all farm machines suffer more from lack of oil than from 

 any other one cause. While the bearings of most farm machines 

 work under comparatively light pressures and do not transmit 

 any great amount of power, in the case of the tractor the reverse 

 is true, and proper lubrication is absolutely essential to satis- 

 factory operation. Furthermore, a careful watch on practically 

 all bearings is a necessity, because a slight looseness here will 

 nearly always cause excessive damage if neglected. Attention 

 to these two items of keeping bearings properly tightened and 

 well lubricated will go a long way toward insuring satisfactory 

 operation of any tractor. 



The early tractors Avere naturally used largely with machines 

 which had been designed for use with horses since no special 

 equipment was available. To-day, however, there is already a 

 rather complete list of specially designed machines for use with 

 tractors, and this is constantly being increased. It goes with- 

 out saying that a tractor does the most satisfactory work when 



