282 Report of the Special Committee. 



soil where we tried it w^as 443 pounds, or 26 pounds more than it 



was without a coulter. We record the experiment exactly as it 



was made, leaving each one to draw his own conclusions; but, in our 



judgment, although the use of a coulter in sod ground makes much 



better work, it does not have much effect on the draught in any way. 



This opinion must, however, be modified with respect to the 



swivel plows, which evidently worked much more easily with a 



coulter, as appears by comparing the results of experiments Nos. 



9' 10 and 11: p,„„^^ 



Experiments Nos. 9 and 10 469 



Experiment No. 11 582 



Difference in favor of coulter 113 



It does not appear from our experiments that the depth of the 

 coulter in the soil, so long as it does not run below the sole of the 

 plow, affects the draught. (See experiments Nos. 12, 13 and 14.) 

 But, if the coulter is used, our experiments show very decidedly 

 that much depends upon its being in a proper condition. On 

 comparing the average of the fifty-sixth, fifty-seventh and fifty- 

 eighth experiments (545 pounds) with the average of the sixtieth 

 aiid sixty-first (512 pounds), it will be seen that 33 pounds were 

 saved by the use of a sharp coulter. 



It was not found that the rake of the coulter made any material 

 difference when plowing among fibrous roots, but it became neces- 

 sary to give it more rake when plowing among rhizomes^ such as 

 quack roots. This fact was well exemplified in experiments sixty 

 and sixty-one (512 pounds). The rake was then increased very 

 considerably in experiments sixty-two to sixty-five (452 pounds), 

 showing a reduction in power of 59 pounds. On examining the 

 edge of the cutter it was found that there was a rough wire edge 

 on it, and it was then rubbed down smooth with a scythe-stone, 

 and the draught fell, in the sixty-sixth and sixty-seventh experi- 

 ments, to 422 pounds. It was then found that the coulter had 

 slipped and lost most of the rake that had been given to it during 

 the last two experiments. It was again adjusted properly, and 

 from the sixty-eighth to the seventy-first experiment the draught 

 w^as 389 pounds. These experiments show a reduction in draught 

 of 156 pounds by putting the coulter in proper order. 



VI. Does the skim plow consume more or less power than the 

 coulter ? 



