18 WELLS'S NATURAL PHILOSOPHY. ' 



The force which holds the particles of a stone, a piece of 

 "What are Ex- •vrood, or metal together, the falling of a body to the earth, the 

 tract^n*? " tendency which a piece of iron or steel has to adhere to a mag- 

 net, are all familiar examples of the dilTerent forms of attraction. 



23. All the researches and investigations of 

 dest^uctibiiT modern science teach us, that it is impossi- 

 ble for any finite agent to either create or de- 

 stroy a single particle of matter. The power to create 

 and destroy matter belongs to the Deity alone. The 

 quantity of matter which exists, in and upon the earth has 

 never been diminished by the annihilation of a single 

 atom. 



When a body is consumed by fire, there is no destruction of matter : it 

 has only changed its form and position. When an animal or vegetable dies 

 and decays, the original form vanishes, but the particles of matter, of which it 

 was once composed, have merely passed off to form new bodies and enter into 

 new combinations. 



PRACTICAL QUESTIONS ON THE PROPERTIES OF MATTER. 



1. Why will water, or any other liquid, when poured into a tunnel closely inserted into 

 the mouth of a bottle, run over the sides of the bottle ? 



Because the bottle is filled with air, which, having no means of escape, 

 prevents the water from entering, since no two bodies can occupy the same 

 space at the same time. Ifj however, the tunnel be lifted from the bottle a 

 little, so as to aftbrd the air an opportunity to escape, the water will then 

 flow into the bottle in an uninterrupted stream. 



2. Are the pores of a body entirely empty, vacant spaces ? 



The pores of a body are often filled with another substance of a different 

 nature. Thus, if the pores of a bod}^ be greater than the atoms of air, such a 

 body being surrounded by the atmosphere, the air will enter and fill its pores. 



3. When a sponge is placed in -water, that liquid appears to penetrate it. Does the water 

 really enter the solid particles of the sponge? 



It does not ; it only enters the pore-?, or vacant spaces between the par- 

 ticles. 



4. When we plunge the hand into a mass of sand, do we penetbate the sand ? 



We do not ; we only disjylace the particles. 



6. Why do bubbles eise to the surface when a piece of sug:ar, wood, or chalk is plunged 

 under water ? 



Because the air previously existing in the pores becomes displaced by the 

 water, and rises to the surface as bubbles. 

 6. What occasions the BJTArpiNG of wood or coal when laid upon the fire ? 



