76 BELL SYSTEM TECHNICAL JOURNAL 



seacoast of northern New Jersey and a radio-telephone set is about to 

 be installed on the steamship "Leviathan" to operate with these shore 

 stations. As this ship approaches or leaves New York it is expected 

 to be possible to talk from it to any telephone in the Bell System. 

 This is intended not only as a demonstration of the technical features 

 of such a service but to afford an indication of the extent to which 

 such a service will be used under commercial conditions. 



Radiotelephony is being used from shore stations to coastal boats 

 in a number of cases in the United States, but not connected to the 

 commercial telephone system. These include particularly certain 

 boats of the U. S. Coast Guard Service. A careful study, including 

 tests, has been made of telephone service to tugboats operating in 

 New York harbor for the purpose of controlling and thus making 

 more efficient the operation of such craft. So far, it is not clear that 

 this service will be commercially justified. 



Telephony to Other Mobile Stations 



Consideration has been given to telephone connections for types 

 of mobile stations other than ships and airplanes. Communication 

 with moving trains can technically be carried out with facilities now 

 available. Active studies are under way to determine the practica- 

 bility of providing such service at a cost which would be attractive 

 commercially and with apparatus which can be limited to a reason- 

 able space on the train. 



Telephone Services of Railroads and Other Public Utilities 



The operation of railway systems requires a large amount of com- 

 munication service. The dispatching of trains was, until recent years, 

 carried out largely by the use of telegraph. This has been rapidly 

 changed until at the present time on over 60 per cent of the total 

 railway mileage the train dispatching is by telephone. The railroads' 

 telephone service to stations in the Bell System is through P.B.X.'s 

 leased to them by the telephone companies. In addition to this, 

 the railroads frequently own private telephone circuits extending 

 along their rights of way which connect to and are switched through 

 these same P.B.X.'s. 



Similar arrangements are provided for meeting the special com- 

 munication needs of electric power companies, oil pipe-line companies, 

 and other utilities. 



Telephone Public Address Systems 



Experience in many cases has shown that with the public address 

 system used by the Bell Companies it is possible to amplify speech 



