36 



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



Marble and Marble. 



"W eight per turn 

 per unit force. 

 Force. ( * ^ 



28 156 196 



14 121 139 



14 117 146 



7 140 137 



7 127 146 



7 134 175 

 Mean = 0-00144. 



, r . c c t j f First cylinder = 14*4. 



Mean circumference ol cylinders < , J , . _ , . _ 



I Second cylinder = 14* 8. 



Marble and Alabaster. 



Force. Marble. Alabaster. 



14 43 31 



7 57 23 



Marble = 0*000050. Alabaster = 0'0027. 



tvt • r j: v j (Marble = 14'8. 



Mean circumference ol cylinders < . _ _ , _ _ _ 



( Alabaster = 16*6. 



Marble and Plaster of Paris. 

 Force. Plaster of Paris. 



14 885 



14 745 



4 905 



Marble less than errors of experiment. Plaster of Paris = - 00844. 



Mean circumference of cylinders < ^- arwe — ^ ^ 



J I Paster of Paris =167 



