XII 

 FUEL FOR GAS TRACTORS 



THE internal-combustion, or gas, tractor is of the 

 greatest importance in the future development of 

 power plowing. We need, therefore, to give con- 

 siderable attention to the question of fuel for this 

 type of motor, since the ultimate success of mechanical power on 

 the farm will depend upon the certainty of an adequate supply 

 of suitable fuel. It is obvious that certain fuels, which are 

 so well adapted to stationary practice, that in some localities 

 they predetermine the type of gas engine, may be utterly im- 

 practicable for use in the gas tractor. We shall discuss in 

 detail, then, only those which may be used economically in 

 plowing. 



By their very nature and source, natural, blast furnace, and 

 city coal and water gases are not suitable for use in portable 

 motors. However, Ocock suggests that the farm tractor's 

 fuel will ultimately come from gas, which will be made directly 

 from waste materials and compressed in tanks. This would 

 allow the temperate zones to use the power of tropical vege- 

 tation, saving the loss of energy encountered in converting 

 raw vegetable materials into alcohol, and alcohol again into 

 gas, but would entail the danger and expense of handling 

 high-pressure tanks. Suction gas producers, making gas 

 directly by drawing steam and air over an incandescent bed 

 of anthracite coal, have been mounted on wheels with great 

 economy of fuel as a result, but have proved too large and heavy 

 to be considered seriously for traction work. Benzol, a volatile 



III 



