134 



THE WHIRLING-TABLE. 



fly-wheel R (fig. 95), which is turned by the handle G, 

 and the motion of the fly-wheel communicates a rapk 

 rotatory motion to the driving- pulley and the shaft. 

 The cord can be stretched or slackened by turning 

 the screw $, which moves a wooden piece upon which 

 the fly-wheel is fixed, either from or towards the shaft, 



according to the direction in 

 which the screw is turned. 



For various experiments, 

 especially on light, it is con- 

 venient to use the plate P 

 in a vertical position. This 

 may be done by fixing the 

 apparatus in the manner 

 shown in fig. 97, or the 

 apparatus is provided with 

 two hinges at c c (fig. 95), 

 which permit the whole to be 

 screwed in a vertical position 

 upon a suitable support. 



The pendulum experiment mentioned in the preceding article may 

 be performed in the following manner. Place the whirling apparatus 

 upon the table so that the lower end of the axle is a few centimetres 

 beyond the edge of the table. Pass one end of a thread about 70 cm 

 long, up through the vertical and laterally through the horizontal 

 hole at the lower end of the axle, and clamp it by driving a little 

 wooden plug into the aperture. Attach the bullet to the other end, 

 start the pendulum, and work the fly-wheel. Even the greatest, 

 speed will not alter the direction in which the pendulum 1-as been 

 set to vibrate in the beginning. 



To the plate of the whirling-table a disc of paste- 

 board is screwed, in which there are six holes, each 6 mtt 

 wide. Two holes are 3 cm , two 6 cm , and two 9 cm distant 

 from the centre. Bullets of lead, or balls of any other 



FIG. 97 (an. proj. ^ real size}. 



