Spraying 



is used and emptied immediately after being filled, 

 but if this is not done such heavy substances as 

 lead arsenate and Bordeaux mixture, where the 

 effective material is not in solution, but in a state of 

 suspension in water, are likely to settle and the 

 spray wUl then be delivered at imequal strengths, 

 and the work will be to a large extent inefEective. 



The pump must be sufficiently powerful to give 

 the necessary pressure, and when spraying com- 

 mences several strokes of the pump should be given 

 before the tap leading to the delivery nozzle is 

 turned on. 



The delivery nozzle is connected to the pump 

 by a length of flexible pipe which must be strong 

 and properly clamped on. By its means the nozzle 

 can be turned in various directions and all parts 

 of the plant covered in turn. The nozzle itself is 

 carried on the end of a metal tube and is one of the 

 most important parts of the machine. There are 

 many patterns, and the exit holes are of many types 

 and sizes according to the work the machine is 

 intended to do, delivering either a coarse spray 

 suitable for lime-washing or a very fine one suitable 

 for Bordeaux spraying. The fine type is most 

 generally useful. It must be easily cleaned, for some 

 of the substances used with it contain fine particles 

 which may sometimes clog it. As a further method 

 of preventing this it is necessary that the machine 

 should be supplied with a strainer, to prevent any 



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