Common Science 



Try to tip the cylinder 

 over. Now stuff some 

 crumpled paper loosely 

 into the cylinder, filling 

 it to the top. Tip the 

 cylinder again. Will it 

 stay on its side now? 

 Force all the crumpled 

 paper to the bottom of 

 the cylinder. Now will it 

 stay on its side? Take 

 out the crumpled paper 

 and lay a flat stone in the 

 bottom of the bell, hold- 

 ing it in place by stuffing 

 some crumpled paper in 

 on top of it. Will the 

 cylinder tip over now? 

 Take the stone out, put 

 the crumpled paper in the bottom of the cylinder, put the 

 stone on top of the paper, and again try to tip the cylinder 

 over. Will it fall? 



The center of the cylinder was always in one place, 

 of course. But the center of the weight in that cylinder 

 was usually near the bottom, because the bell weighed 

 so much more than the paper. When you raised the 

 center of weight by putting the stone up high or filling 

 the cylinder with crumpled paper, just a little tipping 

 moved the center of weight so that it was not directly 

 over the bell on which the cylinder was resting. When- 

 ever the center of weight is not over the base of 

 support (the bottom on which the thing is standing), 

 an object will topple over. Moving the center of 



FIG. 17. So even if the cylinder is laid on 

 its side it immediately comes to an upright 

 position again. 



