409 
1911-12.] On Novel Illustrations of G-yrostatic Action. 
gyrostat shown in fig. 3 both steers and balances the bicycle. It depends 
for its action on the fact that the tube forming the upper part of the fork 
carrying the bearings of the back wheel is attached by means of a sleeved 
joint S to the frame carrying the fork of the front wheel and the gyrostat. 
The bicycle is similar, in fact, to the old-fashioned “ high ” bicycle. 
Stability may be conferred in two ways upon the machine. In the first 
place, the gyrostat may be arranged to imitate exactly the action of a 
human rider. In balancing a bicycle the rider counteracts the tilting of 
the machine by turning the front handle-bar ; if the machine tilts over to 
the left the bar is turned to the left, and the forward momentum of the 
machine and rider, aided by the gyrostatic action of the wheels (the latter 
