Description of the Rotascope. 275 



posed by the persistency of the wheel. If at this moment the pivot 

 be released from the screw, the whole system, composed of the two 

 weights, the frame and ring 3, will be made to revolve by the gravity 

 of the weights, while the ring 2 remains pertinaciously fixed in its 

 position, mitil the wheel has had time again to invert its axes. This 

 time will be greater or less, according to the greater or less velocity 

 of rotation in the wheel, compared with the size of the weights hang- 

 ing over the pullies. 



5. Fix the ring 3 in a vertical position by means of a grooved 

 wedge moving in and projecting above the lower piece of the frame 

 F ; wind up two cords about the pullies on ring 1 , and attach a 

 weight of a few ounces to each ; then set the wheel in rapid motion, 

 and abandon it to the action of those weights. The ring 2 will re- 

 volve in a certian direction about its vertical axis, until the wheel has 

 come to revolve in the opposite direction, then the direction of the 

 ring will be inverted ; — and if the weights continue their action 

 through several revolutions of the ring 1, an inverse motion in the 

 ring 2 will take place at each semi-revolution of the former. If in- 

 stead of revolving about its vertical axis, the second ring be attached 

 and kept at right angles to the plane of No. 3, by cords leading to 

 the side pieces of the frame, these cords will exhibit alternately a 

 strong tension, as the first ring performs its successive semi-revo- 

 lutions. 



6. Hang a weight of one or two pounds on the ring 1, raise it up 

 till that ring is in a horizontal position, (the third ring being still in its 

 vertical position,) and tie a small cord or thread from ring 1 opposite 

 to the end of the axis, down to the lowest point of circle 2. This 

 thread must be strong enough to support the weight before-mentioned 

 on the opposite end of the axis. Now give the wheel a rapid rota- 

 tion ; there will be no tendency in ring 2 to revolve horizontally. 

 But if we cut or burn off the string, so as to allow the weight to act 

 by its whole gravity at the opposite end, the second ring will begin 

 to revolve horizonially with a rapidity proportioned to the weight 

 when the velocity of the wheel is given. 



7. Place the second ring horizontal, hang a weight to its periphe- 

 ry, opposite to the axis of circle 3 ; then having set the wheel in 

 motion, raise the weight up to a level with the centre of the wheel, 

 or even higher, and let it 7'est upon the momenhim of the wheel, until 

 the latter has changed the position of its axis by causing ring 1 to 

 perform half a revolution ; then the weight will descend and oscillate 



