SELECTING MACHINERY AND EQUIPMENT 335 



perhaps one or two acres of trees. Under the best of condi- 

 tions, it entails much heavy labor. 



A modification of the barrel pump is the one-cylinder 

 double-action hand pump or the two-cylinder pump, mounted 

 on a platform, with a vertical handle that the operator moves 

 back and forth. He can put the weight of his body into the 

 action and develop higher pressure with greater ease than with 



(John Bean Mfg. Co.)] 



Fig. 126. A modern duster. The spring platform on which the operator 

 stands takes up shocks and jars and enables the operator to do a steady, 



even job. 



the barrel-mounted pump. The spray material reaches the 

 pump through a suction hose from a barrel or tank. Such a 

 pump will run one lead of hose at 150 to 175 pounds pressure. 

 It will handle up to 5 acres of bearing orchard and is the most 

 satisfactory type of machine if the purchase of a power sprayer 

 is not warranted. It is especially useful in orchards where the 

 trees are only two or three years old, and it does the work 

 rapidly with little waste of material. 



