the Hiah- Tension Magneto. 



293 



On the other hand, the points relating t 2 and C 2 ' do lie on 

 a straight line, but. this line cuts the vertical axis below the 

 origin, instead of above it as would be expected from (2 . 1). 

 This discrepancy (which has been found in similar experiments 

 on other machines) is not easily explained, but it would seem 

 to suggest that the value of L 2 / obtained is likely to be too 

 large. If, however, we take the values given by the lines we 

 obtain 



1^ = 00149 henry; L 2 ' = 62'5 henry; T 2 = O000275 sec. 



Only a single measurement of c is possible, for it must be 

 determined for the normal value of C 2 . c was found to be 

 0-050. 



c was measured with C^O-5, 2*0, 8 - 3 mf.. and the values 

 0-0225, 0-0200, 0-0192 obtained. It is to be expected that 

 c' shonld be rather less than c. L 21 is now found to be 

 0-954 henry, and s' = 1*031. 











Fig. 4. 









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We are now in a position to calculate the peak potential 

 from Prof. Jones's theory on the assumption that there is no 

 damping. These calculated values are plotted against C] in 

 the full line curve of fig. 4 ; i 0i the primary current broken, 

 is taken as 0*5 amp. The points marked © give the values 



