" Skin "-effect in Electrical Oscillators. 



Table III. 



15 



Distance of 

 Oscillator 



from 

 Detector. 



Oscillator; position of detector; and scale reading in mm. 



No. 1. 



No. 9. 



No. 11. 



No. 13. 



cms. 



1 



2 



1 



2 



1 



2 



1 



2 



30 

 40 



50 

 60 



70 

 80 

 90 



50 

 30 



27 

 27 

 23 

 22 

 20 



25 



22 

 26 

 25 

 22 

 20 

 20 



57 

 47 

 35 

 36 

 28 

 31 

 29 



39 

 31 



35 

 32 

 28 

 25 

 26 



50 

 34 



<30 

 29 

 25 



27 

 25 



30 

 24 

 24 

 32 



29 

 26 



27 



63 

 50 

 44 

 44 



35 



48 

 41 

 38 

 43 



35 



It would naturally be suspected that this reversal effect was 

 due to the direct action of the coil or of the connecting wires ; 

 but on removing the cylinders and substituting therefor small 

 knobs no effect was obtained. Indeed the wings of the detec- 

 tor were made at right angles to the wires leading from the 

 coil to the oscillator in order to avoid such action. Moreover, 

 if it were due to the direct action, the effect would have been 

 more pronounced with the spherical oscillators, but such was 

 not the case. 



the table show irregularity in the action 



The readings 



m 



of the oscillators, 



it 



is not 

 a fact 



so great as in 

 due largely to 



various cylinders are 

 of the two readings 



though I believe 

 many experiments with electric waves, 

 the constancy of the interrupter used. 



In Table IV readings obtained with 

 exhibited. Each reading is the mean 



obtained, at the distance indicated, by the detector in its two 

 positions. An examination of the results will lead to the con- 

 clusion that, for frequencies as high as those here used, the 

 effectiveness of an oscillator is not impaired by using a thin 

 shell instead of a solid. 



As stated above, the platinum caps were soldered to the iron 

 and brass cylinders, and were then given an excellent polish. 

 The caps on the gold-leaf and other delicate shells could not 

 be polished in this way. They were simply rubbed clean with 

 chamois. One would naturally expect, therefore, that the solid 

 cylinders would perform best, but such was not the case. 

 Indeed the brass and iron oscillators were the hardest to adjust 

 and seemed about the least effective ; and the gold-leaf acted 

 so continuously better than the solid that I began to think its 

 thinness was a determining factor. The average of the read- 

 ings for gold-leaf given in the table is decidedly better than 



