of Electricity through Gases. 193 



electrostatic units, we must multiply his surface-density with 

 47r/l*25, or very nearly with 10, in order to obtain R. The 

 result is given in Table VI., in which r is the radius of the 

 inner cylinder, in centimetres, and R the normal force when 

 a spark begins to pass. 



Table V. 



Values for Spark-potential between Cylinders. 



I. 



II. 



III. 



IV. 



V. 



VI. 



VII. 



Diameter 



Diameter 





c from 









of internal 



cylinder. 



2r. 



of external 



cylinder. 



2E. 



Explosive 

 distance. 



Bailie's 

 observa- 

 tions. 



47r<r=R. 



Gau gain's 

 formula. 



<r'/<r. 



6-28 



6-86 



•29 



724 



91 



903 



1-25 



5-75 





•56 



844 



106 



9-20 



1-09 



5-50 





•68 



8-73 



110 



9-32 



1-07 



492 





•97 



907 



114 



9-60 



1-06 



492 



5-32 



•20 



9-07 



114 



9-60 



1-06 



4-50 





•41 



8-33 



105 



9-72 



1-17 



440 





•46 



8-25 



104 



9-84 



1-19 



4-00 





•66 



8-59 



108 



10-07 



1-17 



366 





•83 



9-92 



125 



10-30 



1-04 



4-00 



4-45 



•23 



8-23 



103 



1007 



1-22 



366 





•40 



8-60 



108 



10-30 



1-20 



3-10 





•68 



8-95 



112 



10-74 



1-20 



2-49 





•98 



965 



121 



11-35 



1-18 



249 



3-00 



•26 



8-46 



106 



11-35 



1-34 



2-20 





•40 



8-74 



110 



11-73 



1-34 



1-78 





•61 



9-76 



123 



12-40 



1-27 



1-25 





•88 



1099 



138 



13-62 



1-24 



Table VI. 



r. 



R. 



1-5 



110 



•5 



145 



•25 



168 



•05 



282 



•013 



451 



•010 



491 



•0U6 



600 



Comparing these numbers with Table II., we find that the 

 disruption- stress is for two coaxial cylinders not very tar 



