Supplementary Plow Trials. 



269 



Average depth from thirty-ninth to fifty-fifth experiments, both 

 inclusive, 5.64 inches; average width from thirty-ninth to fifty- 

 fifth experiment, both incbisive, 11 inches; average draught 

 from thirty-ninth to fifty-fifth experiments, both inclusive, 463 

 pounds. 



The average draught of the whole series of experiments 

 exceeds the average of the forty-fifth, forty-sixth, forty-seventh 

 and forty-eighth experiments, which agree most nearly with it in 

 the size of the furrow slice, by 20 pounds. 



Recapitulation of Experiments with Plow No. 65 — Flat furrow. 



* Surface draught. 



The average difi'erence in the draught of each inch in depth 

 was 45.20 pounds. 



Experiments to determine the rates of draught to depth made 

 with Holbrook's Plow No. 65. with a coulter adjusted to lap 

 furrows: 



