216 THE ROYAL SOCIETY OF CANADA 



The Cable Used as a Loop for the Reception of Radio Waves 



As an experiment the cable was connected directly to the aerial 

 and ground binding posts of a vacuum tube receiving set; the gal- 

 vanometer and high resistance were, of course, out of the circuit. 

 Thus the cable acted merely as a huge loop aerial of high inductance. 

 When using a detector and a two step amplifier several wireless 

 stations were heard quite easily. The circuit seemed to function best 

 for long waves, 13,000 to 20,000 metres, but waves of higher frequency 

 were also received without difficulty. Though the receiving set 

 was connected up only for a short time, ten or more stations were 

 heard, some of them on the Atlantic sea-board. The radio broad- 

 casting station of Schnectady was heard quite plainly, though the 

 speech and music were somewhat distorted. The remarkable feature 

 was that thefe was practically no static heard, even when using the 

 second stage of amplification on long waves, despite the fact that the 

 static was very bad when the receiving set was used some two hours 

 after on an aerial of the ordinary type. As absolutely no precautions 

 had been taken for the insulation of the cable, which was lying on 

 the ground, partially covered with mud, water and snow, the strength 

 of the signals was quite remarkable. 



Summary 



In the loop were induced currents of various sorts — -power line 

 currents, earth currents, currents due to changes in potential, in 

 magnetic force, and finally, radio-frequency waves. These currents 

 are continually flowing in the cable and vary considerably in magni- 

 tude; those manifestly due to magnetic storms are noted every day, 

 though sometimes they are very faint. 



A cknowledgment 



The author begs to acknowledge his deepest obligations to Sir 

 Frederick Stupart, Director of the Dominion Meteorological Office, 

 who generously lent the requisite apparatus, and to Mr. John Patter- 

 son, who smoothed out all the practical difficulties, and without 

 whose continual help and valuable advice little would have been 

 accomplished. To these friends and to those not mentioned, but 

 whose services were of great value, most heartfelt thanks are due. 



