134 



RECENT ADVANCES IN WIRELESS TELEGRAPHY. 



good radiators electrical oscillations set up by the ordinary spark- 

 discharge method cease or are damped out very quickly by the elec- 

 trical radiation, which removes very rapidly the small amount of 

 their stored-up energy. 



It is well known that if two tuning forks are taken having the 

 same periods of vibration or note and one of them is set in motion 

 by striking it sharj^ly, waves or sounds will form in the air ; and the 

 other tuning fork, if in suitable proximity, will immediatel}^ com- 

 mence to vibrate or sound in unison with the first. 



Of course tuning forks have to do with air waves and wireless 

 telegraphy with ether waves, but the action in both cases is analogous. 



There is one essential condition which must be fulfilled in order 

 that a well-marked tuning or electrical resonance may take place, 

 and it is based on the fact that Avhat we call electrical resonance. 



: ^ 



OTU — ^ 



like mechanical resonance, depends essentially upon the accumulated 

 effect of a large number of feeble impulses properly timed. Tuning- 

 can only be achieved if a sufficient number of these timed electrical 

 impulses reach the receiver. 



Over four years ago the author obtained satisfactory results by 

 increasing the electrical capacity of the radiating and resonating 

 conductors by arranging them at each station in the form of two 

 concentric cylinders, or in other forms of closely adjacent conductors. 

 The electrical capacity of such conductors, as shown in fig. 6, is very 

 large compared with that of a single vertical wire, with the result 

 that the amount of electrical energy stored up in the system referred 

 to in the first case is much larger, and does not radiate or get away 

 in one or two waves, but forms a train of timed impulses which sub- 

 sist for a certain time, which is what is required. 



