THE RELATIVE INTENSITY OF HARMONICS OF 

 A LECHER SYSTEM. (THEORETICAL). 



By F. C. Blakk. 



In the previous paper Blake and Jackson have shown the 

 dependence of tone-intensity upon the edge-on distance between 

 plates. They have found that the optimum condition for each 

 tone is such that, for a given in-put of energy at the oscillator, 

 the energy is distributed among the various tones as follows, 

 the fundamental being taken as 100%: third, 61.63%, fifth 

 21.92%, seventh 6.57%, ninth 2.21%o. eleventh 1.05%. In 

 this paper a theory is given to account for these results. 



Figures 1, 2 and .3 



The theory makes use of the Kirchhoff- Abraham generaliza- 

 tion of Kelvin's formula for the discharge of a condenser. As 

 given in Abraham's "Theorie der Elektrizitat," Vol. II, 2nd 

 edition, we consider electric waves coming from the negative X 

 direction (Figure 1) along two parallel wires that end in a con- 

 denser. Our experimental arrangement was necessarily dif- 

 ferent from that, but if we fix our attention upon the receiver 

 alone and remember that the optimum oscillator-length is 

 different for each tone it is obvious that, so far as the total 

 energy on the receiver is concerned, our arrangement (Figure 2) 

 is identical with Figure 1. 



163 



