286 SUSPENSION OF A BALL BY A JET OF WATER. 



peared to stick to the jet for an instant before letting go ; 

 and having done this once or twice, it stuck to the jet alto- 

 gether, and remained in contact with it, spinning rapidly. 

 The experiment was then repeated with the jet at different 

 distances, and with the larger wheel ; the result was the 

 same in all cases. I found it possible, however, either to 

 increase or to diminish the force of the jet enough to pre- 

 vent the reel from remaining in contact with it. The 

 limits were about 2 and 8 feet. 



In experiment No. 3, the position of the reel when free 

 was carefully marked, so that the least alteration could be 

 noticed, and the jet was placed directly under its centre. 

 In this position the jet did not cause the reel to move to 

 either side in particular, but to oscillate backwards and for- 

 wards. The jet was then pushed slowly forwards, and the 

 motion of the ball watched. At first it moved away from 

 the jet slightly, and remained away until it was struck 

 about 60° from its lowest point, after which it gradually 

 came back to its initial position, which it reached when 

 struck about 65° from its lowest point. 



The forward motion of the jet being continued, the ball 

 began to follow the jet, the point in which it was struck 

 moving upwards very slowly. When the reel finally fell 

 from the jet and came back into its initial position, the jet 

 missed it by about 2^ inches. 



During the experiment the force of the jet was altered ; 

 but within moderate limits this did not affect the position 

 of equilibrium. 



This clearly shows that the position of equilibrium is 

 about 25° from the horizontal circle, and for any deviation 

 below this the equilibrium is much more nearly neutral 

 than for any deviation above it. 



