Stores I6ner0 in Water. 1^1 



pended to it, the pressure of the wire on the 

 ice will gradually liquefy that portion imme- 

 diately under the wire, which allows it to sink 

 into the ice slowly, and as this process goes on 

 the ice freezes together again behind the wire, 

 so that in time the wire will pass entirely 

 through the block and leave it still a solid 

 block, as it was before the experiment began. 



This is an interesting fact which it will be 

 well to remember when we come to explain 

 glacial action, or rather the law that governs 

 glacial action. If we take two pieces of melt- 

 ing ice and bring them together they imme- 

 diately congeal at the point of contact. This 

 phenomenon is called " regelation." Ice has 

 some of the properties of a viscous substance. 

 It will yield slowly to pressure, especially when 

 near the melting point, but if put under a ten- 

 sional strain it will break, as any brittle sub- 

 stance will, so that it has the properties of 

 both viscosity and brittleness. Ordinarily we 

 are in the habit of treating water as a fluid 

 and ice as a solid, but from what has gone be- 

 fore the reader must understand that in a cer- 

 tain sense ice should be treated as having 

 semi-fluidic properties. 



