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^/fs. 



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THE BEGINNINGS OF LIFE. 



8i 



the injured form of a crystal is restored when it is 

 placed under suitable conditions, because such a crys- 

 ^^ cause or ^. talline form is to be regarded as the physical expression 



of that mode of aggregation under which alone (within 



and 



suitable r certain narrrow limits) a polar equilibrium of its mole- 



■es similar ^^^^^ ^^^ ^^'^^ ^' ^^ ^^^^^ ^^ ^°^ ^^ ^ connection 



between particular crystalline forms and certain kinds 



of matter under the influence of given conditions, 



then, what reason would there be for the uniform 



similarity of result which is observable ? Why should 



"■^^ different substances have definite crystalline forms? 



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3ne answer 

 blc doubt 1st 

 rm of the 



Whilst, on the other hand, if a relationship of this 



-d by the mi 



imposes it, a: kind does exist, it is more easy for us to understand 



.-upon attbet that the repair of a broken crystal should be effected 



ctureonceini: with such undeviating regularity. The molecules of 



in the same.:: any kind of matter, when under the simultaneous 



5 only to be s influence of different forces, ultimately tend to lapse 



nduccd by III ^'^^'^ ^ ^^^^^ °^ more or less stable equilibrium 2. 



ons. 



And siffl 



If further proof were needed of the truth of this view. 



ve of the fact 



1st which develf 



(loc. cit..voI.«'[ 



by introauo"?: 



1 circumstance' , 



^ On this subject Mr. Lewes says (loc. cit. p. 623): — 'That it is the 

 polarity of the molecules which, at each moment, determines the group 

 those molecules will assume, is well seen in the experiments of Lavalle, 

 mentioned by Brown (Morpholog.Studien uher die Gestaltung-Gesetze, iS^S). 

 He showed that, if when an octohedral crystal is forming, an angle be 

 cut away so as to produce an artificial surface, a similar surface is 

 produced spontaneously on the corresponding angle, whereas all the 

 other angles are sharply defined.' This cutting away of the angle of 

 the crystal is a change which does not interfere with the essential nature 

 of the crystalline form, so that the polar balance may be perfectly 



ex 



y 



roe 



'<0 



\s^ restored by the formation of another opposing flat surface. 



)0 



ntaneou^^^' 



^ Spencer's ' First Principles,' 2nd ed. pp. 484, 495. 



VOL. II. 



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