Resistance of certain Copper- Tin Alloys. 



557 



To reduce these numbers from a wire to a centimetre cube 

 we must multiply tbem by ? when they become 



7T 



for A 76400 



„ D 75100 



„ E 53500 



„ F 75100 



of which, therefore, A and E agree tolerably with my mea- 

 surements on the rods. 



Matthiessen also measured the conductivity of pure copper, 

 his number when reduced being 



Copper .... 610000 



or about eight times that of pure tin. 



The results may be plotted in order to compare them more 

 readily with the readings given by the induction-balance. The 

 abscissas represent percentages of tin ; the ordinates represent 

 conductivities divided by 1000. 



Specific Conductivities of Copper- Tin Alloys. 



Copper is at a height 610. 



00 

 90 



1 

 In 



■EH 

 IfHj 



In 13 



■ml ■■ 



mm H 



■ ss 



D 



80 



BH H 



^^^^ ^^ 





70 



V 







6C 



\ E i^"" 













50 



*\ i 









V I 







40 



V \ 







30 



\ 







''O 



\ 







10 







c 



1 1 1 1 1 1 1 1 1 



10 20 30 40 o0 60 70 80 90 100 



Percentages of Tin. 



