lOK 



Cnmrnendatore G. Marconi 



[June 2, 



This persistency of the oscillations has been obtained by the 

 employment of tlie system shown in Fig. 6, which I first described in 

 a patent taken out in September 1907. This method ehminates 

 almost completely the spark gap and its consequent resistance, which, 

 as is well known, is the principal cause of the damping or decay of 

 the waves in the usual transmitting circuit. 



DISC DISCHARGER 



Fig. 6. 



The apparatus shown in Fig. 6 consists of a metal disc a, having 

 copper studs firmly fixed at regular intervals in its periphery and 

 ]ilaced transversely to its plane. This disc is caused to rotate very 

 rapidly between two other discs, b, by means of a rapidly revolving 

 electric motor or steam turbine. These side discs are also made to 

 slowly turn round in a plane at right angles to that of the middle 

 disc. The connections are as illustrated in the figure. The studs 



