The Organisation of Matter 



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action of caustic potash, both on vegetable 

 tissues and on tin. 



Temperature exercises a familiar action on 

 living beings. Zero and one hundred degrees 

 centigrade form the extreme limits of organic 

 activity, and this is explained naturally by the 

 properties of water, which constitutes the 

 bulk of all living beings. Between these limits 

 there is always an optimum, a temperature 

 favourable above all others to life. Now in the 

 case of metals their electric sensibility appears 

 also to depend on the temperature; in an ex- 

 ample related by Bose it increases from five to 

 thirty degrees and then decreases to ninety. 

 But it is probable that each metal, like each living 

 being, manifests its individuality by a distinct 

 law of variation. 



We shall close this enumeration with a case 

 in which the analogy is even more unexpected. 

 Sight is the privilege of the higher animals. 

 It is, with thought, the highest form of life. 

 Are we therefore to believe that it evades 

 entirely the laws of inert matter? Many 

 scientists do not think so. Some, taking their 



stand on the existence and the well-known 



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