Spark-Length of an Induction- Coil. 



Table II. — Break-Sparks without Condenser. 



Current broken in primary =2"5 amperes. 



148 



Carbon. 



Zinc. 



Lead. 



Copper. 



Mercury and 

 Platinum. 



Mercury and 



Platinum 



under 



Alcohol. 



Material of 



Primary E.M.F. 



Secondary Spark-length in 



Millimetres. 









Primary Poles. 



in Volts. 



I. 



Slow Break. 



II. 



III. 







Moderately 

 Quick Break. 



Very Quick 

 Break. 





10 

 20 



10-0 



9-9 

 9-75 



110 





28 



8-5 



95 







38 





90 







50 



... 



8-5 





Platinum. 



54 

 70 

 78 

 80 

 90 

 95 



6-0 

 4-0 



7-5 

 70 

 6-5 



10-5 



10 

 26 



28 

 50 

 54 

 60 

 74 

 77 

 90 

 95 



10 

 76 

 95 



10 

 68 

 80 



10 



10 



72 



10 

 72 



•5 



i'-o 



1*5 



1-75 



20 



•3 

 2-0 



2-3 



1-75 



5-0 

 6-5 



7-0 



8-0 



7-5 

 7-5 



7 V 25 



7 V 



68 



6 V 7 



75 

 6-25 



30 

 2-0 



7-75 

 7-25 



125 

 10-5 



190 

 19-5 



8-5 



7-5 



9-5 



8-75 



8-5 

 7-5 



10-5 

 95 



14-5 

 120 



22-0 

 22-0 



