CHAFFEE. — DIPACT EXCITATION OF ELECTRIC OSCILLATIONS. 285 



rent on the primary circuit, and shows that, within the errors of 

 experiment, the assumption is fairly well borne out. 



The remaining dotted curves of Figure 10 are calculated constant- 

 watt curves, and enable one to tell at once the power being delivered 

 under any condition represented by the full line curves of the diagram. 

 Apparently the larger the secondary resistance and the greater the 



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oc 

 ilJ 

 a. 



|3 



50 



40 



30 



> 

 o 



z 



20 



10 



I 

 I 



.6 



lO 12 



AMPERES. 



1.4 



16 



FiGUEE 11. Power and Efficiency Curves with Changing Current, [/o]. 



A2 = 100 meters. 

 Cy = 175 X 10-5 M./. 

 C2 = 86 X 10-5 M./. 



number of turns on the secondary of the helix, the greater would be 

 the power output, but it will be seen that the distance between the 

 constant-watt curves rapidly increases, making it necessary to very 

 much increase R^ and N-^ to give a slightly larger output. Therefore 

 the curves do show the existence of a limit to the power derivable from 

 one gap. These curves also show that with a small number of turns 

 on the secondary helix it is impossible to deliver to the secondary a 

 large amount of power no matter what the resistance is in the 

 secondary circuit. It is clear, as has been said before, that the 

 mutual inductance must be large, and the radiation or resistance large 

 in order to obtain a large amount of power from the secondary circuit. 

 The curves of Figure 8 and those of Figures 9 and 10, which were 

 derived from Figure 8, were taken when the supply current, /o, was 



