Experiments on the Potato-Crop. 



555 



intervals of 6 inches in the row, also exhibited similar advan- 

 tages in favour of the larger sets, viz. : — 



Gross Returns per Acre. 



tons. cwts. qrs. 



Average of 11 varieties, 1 oz. sets .. 13 4 1 



„ 10 „ 2oz. sets .. 15 19 



3 „ 4oz. sets ..22 2 



lbs. ozs. 



20 or 10-85 per set. 

 12 or 13-15 „ 

 3 or 18-11 „ 



After deducting the weight of the sets the net balances of 

 produce per acre stand thus : — 



Every step in each of these three series of experiments gives, 

 without an exception, unequivocal evidence that each increase in 

 the weight of the set produces more than a corresponding 

 increase in the weight of the crop. The following statement 

 will, however, shew that the advantage in the employment of 

 large sets is much less striking in the early than in the late 

 varieties ; out of the examples before given the produce of the 

 early varieties, planted one foot apart in the row, exhibit the 

 following result : — 



Gross Crop. 



Net. 



Average of 7 early varieties, 1 oz, sets 

 „ 7 „ 2 oz. sets 



„ 6 „ 4 oz. sets 



„ 6 „ 6 oz, sets 



„ 2 „ 8 oz. sets 



Although there is throughout an increase over and above the 

 extra weight of the sets, the advance between the larger sizes is 

 not very marked, and is much below that wherein the early and 

 late sets are averaged together. There is even a falling off in 

 the produce of the 8 oz. sets, in comparison with those weighing 

 6 ozs. ; but this is partly from accidental circumstances ; the 

 8 oz. sets being much sprouted before planting, indeed all the 

 larger sets of the early varieties were much more advanced than 

 those of smaller size. After separating the early sorts from the 

 general average results of early and late, given at page 554 

 the average produce of the late varieties, taken separately, will 

 stand as follows : — 



Average of 6 late varieties, 1 oz. sets 

 „ 6 „ 2 oz. sets 



„ 6 „ 4 oz. sets 



„ 3 „ G oz. sets 



„ 4 „ 8 oz. sets 



