IN MODERN SCIENCE. 



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geometrize. Like well-drilled soldiers arrang- 

 ing themselves in ranks, they form themselves, 

 according to regular axes of attraction, in 

 lines diverging at an angle of sixty degrees ; 

 and thus the snowflakes are hexagonal plates 

 and six-rayed stars, the latter often growing 

 into very complex shapes, but all based on the 

 law of attraction under angles of sixty degrees 

 (see Fig. 12). The frost on the window-panes 

 observes the same law, and so does every 

 crystallization of water where it has scope to 

 arrange itself in accordance with its own 

 geometry. But this law of crystallization gives 

 to snow and ice their mechanical properties, 

 and is connected with a multitude of adjust- 

 ments of water in the solid state to its place 

 in nature. The same law, varied in a vast 

 number of ways in every distinct substance, 

 builds up crystals of all kinds and crystalline 

 rocks, and is connected with countless adapta- 

 tions of different kinds of matter to mechanical 

 and chemical uses in the arts. It is easv to see 

 that all this might have been otherwise — nay, 

 that it must have been otherwise — but for the 

 institution of many and complex laws. 



A lump of coal at first suggests little to ex- 

 cite interest or imagfination ; but the student of 



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