232 



B. Davis — New effect produced 



cylinders was perpendicular to the direction of the stream-lines. 

 A scale was placed along the pipe in such a position that the 

 zero was at the stopped end, and the node was at division 48 

 and the middle of the loop at division 24. 



A stroboscopic disc was used to determine the rate of revo- 

 lution. 



Matters being thus arranged, it was found that the system 

 of cylinders when placed in different parts of the closed portion 

 of the pipe rotated with different velocities. A maximum was 

 obtained at the middle of the loop, viz : at 24 and a minimum 

 at either of the nodes, viz : at and 48. The mean results of 

 a set of experiments are given in the table below. 



Position of 



cylinders in 



pipe. 



2 



7 

 12 

 17 

 21 



24 

 26 

 29 

 32 

 37 

 42 

 47 



Eates of 



revolution 



per second. 



•77 



3-53 



6-43 



7-70 



8-74 



9-00 



8-80 



8-47 



8-12 



7-00 



4-69 



•92 



