Kinetic Theory of Solids. 



41 



cent., which I take to be a very satisfactory confirmation of 

 the law. 



The following table needs no explanation now. 



Table IV. 



Temperature 9 

 Lead 



»o/»i 



Temperature 9 

 Magnesium 



Temperature 9 

 Platinum 



njn x 





273° 



373° 



473° 



10 



•971 



•917 



1-044 



1-054 



1050 



1-0 



•956 



•898 



1-052 



1-053 



1054 



10 



•971 



•912 



1-045 



1-056 



1-049 



1-0 



•932 





1-063 



1-047 





294° 



333° 



375° 



1-0 



•924 



•829 



1-318 



1-338 



1-364 



294° 





373° 



1-0 





•955 



1090 





1-102 



273° 



373° 



473° 



1-0 



•982 



•934 



1-018 



1-016 



(•987?) 



T=1330°. 

 Mean 1-05. 

 T = 1230°. 

 Mean 1-063. 

 T = 1310°. 

 Mean P05. 

 T = 1120°. 

 Mean 1-055. 



T = 599°. 

 Mean 1'34. 



T=1023°. 

 Mean 1-096. 



T=2050°. 

 Mean 1-017. 



In the case of iron, if the absolute melting-point 2080, as 

 given by Carnelley, is taken, and Pisati's measurements of 

 rigidity used to calculate N/wj, the agreement is not satis- 

 factory ; thus 



Temperature 273° 373° 473 573° 



(n v 'n 2 1-0 '979 '942 -904 



r ° n jtt>i 1-017 1-011 -993 -978 



but if the melting-point is taken at 1650°, which is within the 

 limit of some determinations, then the values of N come out 



1-028 1-031 1-026 1-028 



with a mean value T028 and a maximum departure of -3 per 

 cent. 



Using the mean values of N/n, just found, and the values 

 of n^ given in Table III., we get the following values of N : — 



Table V. 



10~ 6 N or 10 -6 times the Rigidity at absolute Zero. 



Cu. Ag. Au. Mg. Zn. Al. Sn. Pb. Fe. Ni. Pt. 



452 295 284 104 42fi 264 200 118 771 781 661 



