224 



HYDRAULIC EQUIPMENT 



The ideal type of nozzle, and the one that insures the most 

 sensitive speed regulation and highest economy of water consump- 

 tion is, however, the " axuiliary relief needle nozzle," Fig. 116. 



i 



This consists of a main needle nozzle and a synchronous by-pass 

 in the form of an axuiliary needle nozzle which discharges into the 

 tailrace. Both nozzles are operated by the power mechanism of 



