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ROYAL SOCIETY OF CANADA 



than the softer material inside. The result is that the smaller we 

 draw out a wire the stronger it hecomes in proportion to larger wires 

 of the same material. 



With Constantin, as soon as the load passes the elastic limit, the 

 material shows a slow pulling out, so that no definite extension can be 

 said to correspond to any applied weight. As the load increases this 



t-4 



/ 2 



o/ 



o 



02 



■04 



oà 



C/V/S . 



•OS 



exrc/vs/o/v. 



/o 



/2 



Fig. 3. 



ejffect becomes more rapid, until it becomes quite easy to pull the wire 

 (»ut by just pressing downward on the scale pan with the hand. 



The extensions given for the weights on data sheet A are the 

 total extensions when the wire has pulled out as far as it will go, without 

 waiting over long periods for the stretching to cease. 



(The toughness and strength of this material below the elastic 

 limit, with its property of a very low resistance-temperature coefficient, 



