of the Resistance of Imperfectly Purified Sulphur. 471 



Date. 



1888. 



Temperature 

 of room. 



No. of small 

 cells used. 



E.M.F. of set 

 of small cells. 



E.M.F. of large 

 cell short-cir- 

 cuited through 



10,000 L. ohms.* 



Oct. 20 ... 



20 ... 



21 ... 

 21 ... 



o 



17-0 C. 

 170 C. 

 16-2 O. 

 16-2 0. 



20 

 40 

 40 

 20 



volts. 

 28-661 



57-312 



57-312 

 28 661 



volts. 

 1-432 



1-432 



1-432 



1-432 



Date. 



1888. 



Resistance 



taken out 



of S. 



Thickness 



of layer of 



sulphur. 



Area of 

 layer of 

 sulphur. 



Resulting specific resist- 

 ance of the sulphur. 



Oct. 20 ... 



20 ... 



21 ... 

 21 ... 



L. ohms. 

 90 



15-0 



10-7 



5-8 



centim. 

 0-05 



005 



05 



005 



sq. centim. 

 189-8 



189-8 



189-8 



189-8 



8-575 X 10 13 1. ohms. 

 10-286 XlO 13 „ 

 13-307 Xl0 13 ., 

 14-425 XlO 13 „ 



* Lord Rayleighhas kindly pointed out to us that by a mistake in our method 

 of reduction we have slightly underestimated tins value. The result will be that 

 the absolute value of the resistances as given are very slightly too large. 



The following is a sample of the readings taken : — 



Deflexion of Galvanometer with current from 20 Clark Cells 

 sent through the Sulphur. 



Dene 



xion. 













Double 

 deflexion. 



Zero from 

 deflexion. 



Observed 

 zero. 







Eight. 



Left. 









Divs. of scale. 



Divisions. 



Divisions. 



Divisions. 



Divisions. 



+60 



+ 145 



85 



+ 102 



+ 95 



+ 50 



+ 145 



95 



+ 97 



+ 100 



+ 60 



+ 148 



88 



+ 104 



+ 100 



+70 



+ 150 



80 



+ 110 



+ 100 



+65 



+ 143 



78 



+ 104 



+ 100 



+75 



+ 150 



75 



+ 112 



+ 98 



+68 



+ 143 



75 



+ 107 



+ 98 



+70 



+ 135 



65 



+ 102 



+ 90 



+40 



+ 135 



95 



+ 87 



+ 88 



+60 



+ 140 



80 



+ 100 



+ 85 



+45 



+ 133 



88 



+ 89 



+ 85 



+35 



+ 115 



80 



+ 75 



+ 80 



