CENTRIFUGAL RAILWAY. 



149 



>wer portion is a circle, or, more correctly, the spiral 

 iread of a screw. A ball of lead or glass, placed 

 it the top of the groove attains a certain velocity in 

 lescending the incline which forms the first portion 

 of its path. On reaching the curved portion, it 



FIG. 105 (an.proj. real size). 



tends to move with this velocity in a tangential 

 direction, in virtue of its inertia ; but being impelled 

 to follow the curved path, it is pressed against the rail 

 more strongly by centrifugal force than it is acted upon 

 by gravity, so that even at the top of the spiral it will 

 remain in contact with the rail. 



