PHYSICAL PARADOXES. 



The water tends to freeze ; but as this involves 

 the arrangement of its molecules in positions 

 corresponding to its rigid, crystalline, or solid 

 state, in which their distances from one another 

 are increased, the whole mass would have to 

 occupy more room, to permit of freezing. As 

 more room is not available, freezing cannot 

 occur. But with the increasing cold the mole- 

 cules, in their tendency to take up the 

 new arrangement, keep pressing against one 

 another and against the walls of their prison 

 with continually increasing force, until at 

 last they burst the enclosure at its weakest 

 part. 



This is the thin copper disc. A smart report 

 is heard when it yields, showing the force with 

 which it has been ruptured. 



The chamber having now been forced open, 

 the molecules have room to re-arrange them- 

 selves in a crystalline form, and the water is 

 suddenly converted into ice, with which the 

 whole chamber is filled, while the excess quan- 

 tity (its volume being greater than that of the 

 original water) is forced out through the hole 

 in the copper disc in the form of a long slender 

 column of ice, which projects through the 

 hexagon nut. 



The same results can thus be produced 

 by opposite causes. If we heat water hot 

 enough in a strong iron vessel, we burst the 

 boiler through the formation of steam. If we 



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