24 Prof. E. Edlund on the Path of Electrical Induction- and 

 Experiment 22. 



Deflections. 



Mean . . 27*1 34*2 25*8 



Experiment 23. — The following observations were then made, 

 after the machine had been somewhat altered and the conductions 

 had been reversed, so that the deflections would be towards the 

 opposite side : — 



The disk The disk The disk 



negative. positive. negative. 



The disk 



The disk 



The disk 



negative. 



positive. 



negative. 



f'28-9 



36-6 



27-4 



27-9 



341 



259 



! 27-4 



31-9 



24*6 



24.0 



34-1 



25-4 





f35-4 



47*3 



36-5 



Deflections.- 



{ 34-7 



46-3 



36-7 





[34-0 



44-3 



35-7 







42-0 



36<2, 



Mean . . 347 45*0 36*3 



Experiment 24. — The conical brass point was removed, and 

 in its place a glass tube 3 centims. in length enclosing a plati- 

 num wire a millimetre in diameter was screwed on. The wire 

 reached exactly to the end of the glass tube. Three series of ex- 

 periments were made with this, in which the length of the spark 

 was 1, 2, and 3 millims. It is sufficient to give here only the 

 last, mean numbers : — 



Length of the 



The disk 



The disk 



spark. 



positive. 



negative. 



f 1 millim. 



120 



8-1 



Deflections. •< 2 millims. 



26-2 



19-2 



1 3 „ 



47-5 



37'6 



Erom Experiments 22 to 24, it follows with certainty that the 

 disjunction-currents are strongest when the positive electrical dis- 

 charge proceeds from the disk to the point. The cause, as has 

 already been stated, is that in this case the disintegration of the 

 pole-surfaces is most powerful. It is clear that the difference 

 between the two disjunction-currents must become smaller if in- 

 stead of a brass disk a similar one be used of another metal which 

 is more easily disintegrated, so that the mechanical work which 

 the discharge performs in producing the disintegration will be 

 less considerable. If instead of the brass disk a mercury surface 

 be used, the mechanical work which the discharge produces in 

 the spark will consist mainly in imparting velocity to the par- 



