SOLIDS DEFYING GRAVITY. 



top A is coming forward, the bottom B is going 

 backward, the front is going down, and the 

 back up. Let the knob C at the left extremity 

 of the axis be resting in a small cup on a pillar 

 support. 



Depress the other knob D, or leave gravity 

 to depress it, tilting the right hand end of the 

 axle downwards towards E and the top of the 

 gyroscope to the right towards F. If the top 

 of the gyroscope were previously still, this 

 tilting would give it a movement in the direc- 

 tion of the dash line towards G. But it was 

 not previously still. In virtue of the spin of 

 the gyroscope the top part had a movement 

 directly forwards and then downwards in the 

 direction towards the arrowhead H. And this 

 movement it is not willing to resign in favour 

 of the movement towards G. Like all other 

 moving things, it tries hard to keep to its 

 original direction of movement towards H. 

 The most that it will agree to, except under 

 constraint of great violence, is a compromise 

 in the form of a movement in the direction of 

 the dot line towards the middle arrowhead. 



In doing this it is coming down to the right 

 of its original direction ; and it cannot do this 

 unless the front rim of the gyroscope goes 

 round to the right that is to say, unless the 

 right-hand end of the axis goes backwards. 



Thus it happens that if we press D down- 

 wards towards E, it tends, apparently of its 



D 33 



