THE SIPHON 



119 



FIGURE 65 



support a column of water about 34 feet high. But since it 

 is impossible to create a perfect vacuum with the piston and 

 valves, water never rises as high as this in 

 a lift pump. In practice the average limit is 

 about 27 feet. 



The Siphon. Experiment 60. Fill an eight- 

 ounce bottle with clean water and fit it tightly 

 with a two-holed rubber stopper. Through one of 

 the holes in the stopper insert a tightly fitting 

 glass tube, which reaches nearly to the bottom of 

 the bottle and extends an incji or two above the stopper. Attach 

 to this glass tube a clean rubber tube which is long enough to reach 

 below the bottom of the bottle. Fit a sealed glass tube so that it 



can be readily in- 

 serted in the open 

 hole of the stopper. 

 (Figure 65.) 



" Suck " water 

 out of the end of 

 the rubber tube 

 hanging below the 

 bottom of the 

 bottle. As soon as 

 the water begins to 

 flow, withdraw the 

 mouth without rais- 

 ing the tube. The 

 water will still con- 

 tinue to flow. In- 

 sert the sealed glass 

 tube in the open 

 hole of the stopper. 

 The water stops 

 flowing. Pull out 



A GREAT SIPHON IN THE Los ANGELES tne S lass P lu - The 



AQUEDUCT water begins to 



