Shin "-effect in Electrical Oscillators. 



17 



The magnetic nature of the iron made no difference what- 

 ever ; iron and brass were indistinguishable in their behavior. 

 Silver did not appear equal to platinum as a spark-surface. 



As the experiments with cylindrical shells failed to exhibit 

 any trace of the " skin "-effect, it was decided to try with 

 spheres, and Righi oscillators with spheres 2*5, 4, and 10 cms , 

 respectively, in diameter were constructed. By these solid 

 brass spheres were compared with gold-leaf spherical shells of 

 the same diameter. The latter were made by covering with 

 gold-leaf accurately turned and beautifully polished lignum- 

 vitae spheres of the required sizes. 



Table V. 

 Spheres 2*5 cms in Diameter. 



Distance of 





Detector position ; ai 



id scale reading 



s in mm. 





Oscillator 

























from 





T 



II 



III 



IV 





Detector. 















cms. 



1 



2 



1 



2 



1 



2 



1 



2 











1. 



Solid 











30 



40 



44 



41 



40 



46 



39 



46 



35 



41-4 



50 



27 



23 



24 



23 



18 



20 



25 



25 



23-1 



100 



15 



13 



12 



8 



11 



10 



12 



13 



11-8 



140 



10 



7 



9 



7 



8 



8 



11 



7 



8-4 



200 



7 



7 



7 



4 



7 



4 



10 



5 



6-4 



250 



7 



5 



6 



5 



5 



7 



8 



6 



6'1 



300 



7 



6 



5 



4 



4 



5 



4 



5 



5-0 









2. 



Shell. 













30 



39 



40 



46 



37 



40 



41 



50 



45 



42-3 



50 



18 



22 



20 



16 



22 



24 



27 



28 



22-1 



100 



10 



12 



10 



12 



13 



13 



16 



15 



12-6 



140 



8 



7 



8 



7 



8 



7 



12 



12 



8*6 



200 



6 



4 



6 



5 



5 



5 



15 



9 



6-9 



250 



6 



6 



6 



4 



7 



5 



10 



11 



6-9 



300 



5 



7 



5 



7 



4 



3 



10 



8 



6*1 



In the oscillators composed of solid spheres the brass surface 

 was used as sparking faces. Observation showed that, in air, 

 newly polished brass is at least equal and possibly superior to 

 sheet platinum, and the oil dielectric prevents the rapid 

 deterioration of the surface. 



For the gold-leaf shells platinum faces were necessary. Two 



Am. Jour Sci.— Fourth Series, Vol. XIII, No. 73 — January, 1902. 

 2 



