Smithsonian Report. 1942. — Fleming 



Plate 7 



CONDUCriNG f/eC'Orj 

 PROPOSED B>' »i:uN€L 

 AfJD HEAVISIDC 



WITH RCFUCTING REGION 

 IN. THE OUTER ATMOSPHCRE 

 RADIO WAi/ES CAN BE 

 RECEIVED AROUND 

 CURVED SURFACE 

 OF The EARTH 



HilTHOur REFLECTING REGION 

 RADIO WAVES WOULD TRAVEL 

 OUTWARD INTO SPACE AND 

 WOULD NOT CURVE AROUND 

 THE EARTH 



PATH OF LOW FREQUENC 

 (least PENETRATING) 



-TRANSMITTER 



UPPER EARLY Evidence for Electrically Conducting Resign ; lower. 

 Paths of Radio \Nf^\j^s. of Different Frequencies in the Upper atmos- 

 phere OR IONOSPHERE. 



