Dr. F. T. Trouton. An Experimental [Nov. 21, 



Quartz and English Plate Glass. 



Force. Quartz. Glass. 



28 46 107 



28 32 103 



28 46 100 



28 42 100 



28 36 100 



Quartz = 0-000040 Glass = 0*000102 



Mean circumference of cylinders I Q uai ^ z ^4 

 J I Glass = 17-0 



Quartz and French Plate Glass. 



Force. 



Quartz. 



G-lass. 



14 



57 



135 



14 



50 



139 



14 



42 



123 



14 



57 



167 



7 



58 



126 



= 0-000053 





Glass 0-000138 



Mean circumference of cylinders <f Q^ ar,; ' z ^ ^ 

 J I Glass = 16-7 



Quartz and Serpentine. 



Force 28. Mean of five experiments ( f mrtz . = °' ™ ™ 



F I Serpentine = 0-000402 



Mean circumference of cylinders l Q uar * z 1^4 

 J I Serpentine = 17*3 



Quartz and Marble. 



Force 28. Mean of two experiments { ®™i\ z = ^00006 



^ I Marble = 0*00114 



Mean circumference of cylinders <f Quartz ~~ ^ 

 J [Marble = 14'8 



Quartz and Alabaster. 

 Force. Alabaster. 

 28 32 

 14 26 

 14 28 

 7 24 

 4 26 



Quartz less than errors of experiment. Alabaster = 0'0027 



Quartz = 17'4 

 Alabaster =16*6 



Mean circumference of cylinders < 



