614 BELL SYSTEM TECHNICAL JOURNAL 



With the first transoceanic circuit estabHshed, further circuits 

 followed rapidly. For a number of years prior to 1927 investigations 

 had shown that short waves could travel enormous distances with 

 very much less attenuation than the long waves. Telephone engineers 

 conducted a series of long distance tests which laid the foundation for 

 developing circuits on these short waves with much less power. As a 

 result a short wave transoceanic telephone circuit, the first of its kind, 

 was opened on June 6, 1928, between the United States and England. 

 The Germans followed by establishing a circuit to Buenos Aires in 

 December of that year. The Dutch established one to Bandoeng in 

 January of the following year, 1929. Then another circuit was opened 

 up between the United States and London in June of 1929. The 

 circuit from Madrid to Buenos Aires was established that same year, 

 and there followed very rapidly circuits from London to various 

 British Colonies, a circuit from New York to Bermuda, and one from 

 San Francisco to Honolulu, so that as of Jan. 1, 1939 the world was 

 covered by a multitude of circuits as indicated in Fig. 2* However, 

 the radio circuits of greatest interest to us are those circuits extending 

 from this continent to other continents. These appear in Fig. 2. 

 There are several channels to London, one to Paris (temporarily 

 suspended), one to Rome, one to Australia (temporarily suspended), 

 one to Berlin, one to Switzerland, two channels to Honolulu and a 

 number of circuits to South and Central American countries, circuits 

 to Manila, Bandoeng, Tokyo and Shanghai. There is a circuit from 

 Montreal to London operated by the Canadian Marconi Company 

 and British Post Ofifice. The facilities are now such that from almost 

 any telephone in the United States it is physically possible to talk 

 to almost any telephone in the rest of the world, although due to 

 censorship some of the circuits are not actually in use. 



Another use for radio as a link in telephone service is for providing 



service where wire circuits would be unusually expensive and difficult 



to maintain. Such a circuit indicated in Fig. 2 runs from Seattle to 



Juneau, Alaska. It is operated by the Signal Corps and connects 



with the general telephone system at Seattle. Another circuit is 



shown in Fig. 3 which runs from Green Harbor to Provincetown, 



Massachusetts, a distance of 24 miles across Cape Cod Bay. This 



circuit supplements the wire lines which reach Provincetown by a 



roundabout path by land around the south side of the Bay. The 



radio link provides a very desirable alternate route to points on the 



Cape and has been useful in a number of emergencies in maintaining 



* Explanation. — On account of unsettled conditions, has not been brought up- 

 to-date. 



