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done similarly, but two mixing-tubs will be sufficient in 

 which to prepare the mixture. 



The quantity necessary to apply per acre varies from 

 80 gallons on a very young crop of small-topped 

 varieties, to 200 gallons on strong, coarse-haulmed 

 varieties. The cost of materials to make the solution 

 is about 4s. for 100 gallons. 



Use of the Sprayer. 



The nozzles of the sprayer should be carried well 

 down towards the base of the stem, and the nozzles 

 should be turned upwards so that the spray may be 

 directed to the under side of the leaves, where the 

 attack is most commonly made. The spray should not 

 be directed too vertically, or the upper leaves will not 

 receive the spray. A slightly horizontal spray will 

 affect the next row to some extent, but this will be 

 counterbalanced when treating with the next row. If 

 a horse-machine is carefully observed at work a cloud 

 of spray can be detected, and this ensures all parts 

 being affected. If the nozzles are placed too vertically 

 the spray gets little opportunity of breaking, as it is 

 driven bodily on to some part of the plant, and is to 

 an extent wasted. A very thin film of the mixture 

 prevents attack, but if it is too thick the stomata are 

 blocked, and cannot fulfil their functions. When 

 setting the nozzle it is important to notice that the 

 spray does not expend itself on the ridges of earth, but 

 on the rows of potatoes. 



We find that by attaching two pairs of nozzles to- 



