190 matured dfcfracles. 



remains in the liquid state, it may be suddenly 

 congealed by taking off the pressure; this 

 shows that the pressure helps to hold the mole- 

 cules in the position necessary for the liquid 

 state, and prevents the rearrangement of them 

 that takes place at the moment of freezing. 

 When the water molecules are arranged for 

 the liquid condition they may be compared to 

 a spring that is wound up and held in position 

 by the heat energy that is stored in the water. 

 And when this energy is given up to a certain 

 degree the power that holds the spring wound 

 up is suddenly released, when it unwinds and 

 occupies a larger space. There is a force that 

 we may call polar force, which is constantly 

 tending to push the molecules of water into an 

 arrangement such as we see when crystalliza- 

 tion takes place as it always does in the act 

 of freezing. These polar forces cannot act so 

 long as the energy in the form of heat is suffi- 

 cient to hold the water in the fluid state. But 

 the moment this energy, which tends to hold 

 it in the fluid state, falls below that which 

 tends to rearrange it into the crystalline form, 

 it is overcome by the superior power of the 

 latter force, and we have the phenomenon of 

 solidified water. 



A very interesting experiment may be per- 

 formed with a block of ice by anyone when the 

 ice is near the melting point. If a wire is put 

 around the ice and a sufficient weight is sus- 



