38 SCIENTIFIC RECREATIONS. 



inertia in the broomstick. The shock suddenly given, the impulse has not 

 time to pass on from the particles directly affected to the adjacent particles ; 

 the former separate before the movement can be transmitted to the glasses 

 serving as supports.* 



The experiment represented in fig. 31 is of the same nature. A 

 wooden ball is suspended from the ceiling by a rather slender thread, and a 

 similar thread is attached to the lower end of the ball. If the lower thread 

 is pulled forcibly it will break, as shown in the illustration ; the movement 

 cammunicated to it has not time to pass into the ball ; if, on the contrary, 

 it is pulled very gradually and without any shock, the upper thread instead 

 will break, because in this case it supports the weight of the ball. Motion is 

 not imparted simultaneously to all parts of a body, but only to the particles 

 first exposed to a blow, for instance. One might multiply examples of this. 



Fig. 32. Extracting a " man " from a pile of draughts without overturning the pile. 



ilf a bullet be shot from a gun, it will make a round hole in a piece of wood 

 or glass, whilst if thrown by the hand, that is to say, with much less force, 



* The experiment we have just described is a very old one. M. V. Sircoulon has told us 

 that it was described at length in the works of Rabelais. The following remarks are in 

 " Pantagruel," book II., chap. xvii. 



" Panurae then took twojjlasses of the same size, filled them with water, and put one on 

 one stool, arid the other on another, about five feet apart, and placed the staff of a javelin 

 about five-and-a-half feet long across, so that the ends of the staff just touched the brim of the 

 glasses. That done, he took a stout piece of wood, and said to the others : " Gentlemen, 

 this is how we shall conquer our enemies ; for in the same way that I shall break this staff 

 between these two glasses, without the glasses being broken or injured, or spilling a single 

 drop of water, so shall we break the head of our Dipsodes, without any injury to ourselves, 

 and without getting wounded. But that you may not think there is magic in it, you, Eusthenes, 

 strike with this stick as hard as you can in the centre." This Eusthenes did, and the staff 

 broke in two pieces, without a drop of water being soilt. 



