188 SPRAYING APPARATUS 



can be done with an ease and comfort and thoroughness im- 

 possible with the short lengths (see types of couplings, Fig. 86). 

 The Extension Rod. — In addition to these more important 

 parts the outfit should have an extension rod on each lead of 

 hose. This may be either an iron rod or a bamboo lined with a 

 brass tube. The latter is preferred because it is much lighter 

 and its larger size makes, it easier to handle, but the iron rod is 

 certainly much cheaper and does not break as easily. There 

 should also be at least one, and preferably two cut-offs for each 

 lead of hose. It is absolutely necessary to have one at the base 

 of the extension rod so that the operator may shut off the liquid 

 at will, and it is very desirable to have a second one at the 

 pump, if there are two lines of hose, so that in case of accident 

 to one line it may be shut down for repairs, while the other may 

 continue to operate. 



QUESTIONS 



1. \^niat are the good and bad points of the bucket ijump? 



2. Discuss the knapsack sprayer. 



3. What can you say of the barrel pump? 



4. Give the important points of a good barrel pump. 



5. What are the advantages of the double-action liand pump? 



6. Name the different types of power sprayers. 



7. Give the special advantages of each type. 



8. Describe the Vermorel type of nozzle. 



9. What are the advantages of the disc type of nozzles? 



10. ^^^ly is an angle nozzle preferred to a straight one? 



11. Give some points to be considered in the purchase of spray hose. 



12. What type of extension spray-rod would you prefer? Give reason. 



13. What power sprayers and what type of hand sprayers are used in 



your section? 



