CHARACTER OF A GOOD PLOW. 121 



N". Y. Good steel plows cost about double those made 

 of cast-iron. 



CHARACTER OP A GOOD PLOW. 



Every good plow should possess two important quali- 

 ties. The first relates to its working. It should be easily- 

 drawn through the soil, and run with unifonn depth and 

 steadiness. The second refers to the character of the work 

 when completed. The inversion of the sod, especially if 

 encumbered with vegetable growth, should be complete 

 and perfect ; and the mass of earth thus inverted should 

 be left as thoroughly pulverized as practicable, instead of 

 being laid over in a solid, unmoved mass. This is of the 

 greatest importance on heavy soils, and is highly useful 

 on those of a lighter character, except, it may be, clear sand 

 or the lightest gravels. The harrow, at best, is an imper- 

 fect loosener ; it pulverizes the surface, but its weight, and 

 that of the team, press down the mass below. Whatever 

 loosening, therefore, can be accomplished in plowing is a 

 gain of vital importance. 



THE CUTIIXG EDGE. 



The point and cutting edge of the plow perform the first 

 work in separating the furrow-slice from the land. It is 

 important that this edge should not only do the work well, 

 but with the greatest possible ease to the team. The force 

 required to perfomi this cutting is greater than many sup- 

 pose. The gardener who thrusts his sharp spade into the 

 hard earth uses more force than afterwards in lifting and 

 inverting the spit. We may hence infer that a large part 

 of the power of the team is expended in severing the fur- 

 row-slice. This inference has been proved correct by the 

 use of the dynamometer, in connection with carefully con- 

 flucted experiments, which have ^hpwn the force usually 

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