C. B. WARRING. 103 



except the last, excites so much surprise. The thing 

 seems to be alive. Somebody has compared the feeling 

 to that which would be produced by the squirming of a 

 serpent trying to escape from one's hands. In face, with 

 a large instrument, it will sometimes, by its unexpected 

 movements, throw itself out of the hands of an inexpe- 

 rienced holder. 



12. If, while the gyroscope is balanced, as in fig. 2, 

 the wheel be set in rapid motion, the ring and arm will 

 remain at rest. 



Now, attach a string at c, and pull downwards. The 

 instrument will move horizontally in the direction in 

 which the bottom of the wheel is going. 



Pull the string upwards, the instrument will move in 

 the same direction as the top of the wheel. 



Pull the string horizontally towards you, and at right 

 angles to the axle ; the instrument goes vertically up- 

 wards. 



Pull the string from you, but still horizontally ; the 

 instrument falls. 



In each case, the resulting movement is at right angles 

 to the pull, continues while the pull lasts, and ceases 

 when the pull ceases. . In every case, however, there is 

 a small movement in the direction of the pull. 



13. Sometimes the gyroscope stands out for many 

 seconds, as if in doubt whether to go up or down. Then 

 it begins slowly to rise, gyrating more and more rapidly 

 as it goes up, till it reaches a vertical position, when both 

 wheel and ring spin around for a while like a top. After 

 a short stay it begins to descend in widening circles. 



The top-like spinning of the ring ceases as it leaves 

 the vertical, and in a few moments the instrument conies 

 to rest as it strikes the table. 



This experiment is best performed as follows : Instead 

 of the standard, use a pane of glass laid flat on the table. 

 Set the wheel in motion. Place the gyroscope on the 



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