1908.] 



on Transatlantic Wireless Telegra2ihy. 



123 



the initial long-distance tests. I must also add that I have, for 

 many years, had the benefit of the advice of Dr. J. A. Fleming, 

 of the University of London, whose experience on all matters dealing 

 with high-tension work and electrical oscillations is universally 

 acknowledged. 



The wave-length used during these tests was 12,000 feet, the 

 capacity employed 1 * 6 microfarads, and the potential to which the 

 condenser was charged 80,000 volts. 



Good signals were obtained at Cape Breton from the very com- 

 mencement of the tests, but some difficulty was encountered in 

 consequence of the effects of atmospheric electricity due to the 

 prevalence of thunderstorms in the eastern part of Canada during the 

 first few days of the tests. 



nc i:v 



Simultaneously with these tests others were carried out from 

 Poldhu to Glace Bay with a new system of transmitting apparatus, by 

 means of which continuous or semi-continuous oscillations could be 

 produced. 



Proportionately to the energy employed the signals from Poldhu 

 were so much better than those from Clifden that I decided at once 

 to adopt this new method of transmission at Glace Bay and Clifden. 

 The apparatus which I have been using for producing continuous 

 or closely adjacent trains of electric oscillations is as follows : — * 



A metal disc A (Fig. lo), insulated from the earth, is caused to 

 rotate at a very high speed by means of a high speed electric motor 

 or steam turbine. 



Adjacent to this disc, which I shall call the middle disc, are 



Patent Application No. 20,119, September 9, 1907. 



