RECENT ELECTRICAL DISCOVERIES 115 



after-glow of the setting sun, and the why of the 

 zodiacal light." 



He says the corpuscles seem to be solving the big 

 problems of the heavens, and adds : " The corpuscles 

 become luminous when impinged upon by electric 

 waves; and waves of light, which are electro-mag- 

 netic disturbances, must move them, and light will 

 be produced and be scattered in all directions as 

 if reflected from minute particles of ordinary mat- 

 ter. This may account for the glow of the nebulae, 

 and the zodiacal light. These corpuscles, being ad- 

 mitted into the moist air of our earth, form nu- 

 clei of condensation and drops are formed; and 

 the growth of the high, fleecy clouds finds its be- 

 ginning around these corpuscles. They also strike 

 our equatorial region; there they are influenced by 

 the earth's magnetic forces and deflected towards 

 the poles, and near the poles they reach gases 

 dense enough to become luminous by their impact 

 and show the fantastic colorings of the aurora. 



" Our atmosphere lies, then, like a great insulating 

 sheet between conducting layers the surface of the 

 ocean and the upper air. In the ether of this inter- 

 mediate insulating region electric waves may be 

 set up to be propagated as signals in straight lines 

 in all directions. When wireless telegraphy first 

 reached out timidly into space, we all said its cur- 

 rents would leave the earth's surface within a short 

 distance, for they went out from the earth's surface 

 in straight lines; but as they extended farther and 

 farther they seemed to bend around the earth and 

 to follow its curvature. Hertz, who discovered the 

 electric waves which Marconi now so successfully 

 uses in wireless telegraphy, showed us in 1887 that 



