WORKING WONDERS WITH A TOP 



right angles, in reality displaces it horizontally. Such 

 displacement brings it in contact with one of the 

 flanges, and the revolution of the gyroscope itself 

 tends to make the axis roll along this flange. But 

 this roll virtually constitutes a longitudinal thrust 

 on the axis of the gyroscope; and such longitudinal 

 thrust of course results in lifting the axis vertically. 

 This lift brings another part of the axis in contact 

 with another flange attached to the car body, and 

 pressure against this tends to lift the car back to the 

 level, while at the same time the reaction on the gyro- 

 scope causes it to precess back to its original position. 

 An incessant cycle of operations of which this is the 

 epitome serves to maintain the car in equilibrium. 



A single gyroscope would suffice for this if the car 

 were running on a straight track. But on rounding 

 a curve a disturbing force would be brought to bear 

 on the gyroscope, due to the changed direction of the 

 train, which would result in tipping the car abnor- 

 mally. To prevent this, a second gyroscope is in- 

 stalled, which will aid the first in balancing on a 

 straight-away course, and counteract the abnormal 

 tipping at the curves; such counteraction being due 

 to the fact that the two gyros revolve in opposite 

 directions. 



The balancing feats actually performed by Mr. 

 Brennan s gyro-car are striking, not to say mystify- 

 ing. If you push against the side of the car with your 

 hand, the car is felt actually to push back as if resent- 

 ing the affront. If the wind blows against the car, it 

 veers over toward the wind. If the track on which it 

 runs consisting in the case of the model car of an 



