THE PLOW OF WATER IN WOOD-STAVE PIPE. 



19 



-Open fo air. 



z"*&")¥i.P/pe 

 '/a hole 



C.I.P^^jbrajed. 

 pFi'bre washer. 



PCScobe 



Fig. 3. — ^Method of attachiug mercury manometers to wood-stave pipes. Details of menometers, fluores- 

 cein gun, and combined corrent meter xroight and mercnry bottle. 



