368 BELL SYSTEM TECHNICAL JOURNAL 



reduce the dielectric losses. iVlso, the loading coils were somewhat better 

 than expected. In a report to Gherardi, Jewett wrote: 



"These tests indicate a most successful and gratifying outcome for a piece of 

 work which has taxed our energies almost to the limit and which it must be ad- 

 mitted was an extremely large experiment at the time the original decision to lay a 

 cable was made. The results obtained seem to me conclusive proof, if such proof 

 is still needed, of our abiHty to forecast transmission results without recourse to 

 laboratory demonstration ..." 



It is of interest to note that the attenuation in the 10-gauge cable circuits 

 was approximately ^ lower than that of non-loaded 104 mil open-wire cir- 

 cuits, and only 50% higher than that of loaded 104 mil and non-loaded 165 

 mil open-wire. The attenuation in the 13-gauge circuits was approximately 

 70% higher than that in the 10-gauge circuits. 



Considerable telegraph flutter was noticed in the long cable circuits when 

 they were used simultaneously for telephony and telegraphy. This led to 

 the restriction of the magnitudes of the superposed telegraph currents and 

 to the development of more sensitive telegraph relays. Several years later, 

 (1916), the development of more stable types of loading coils proved to be 

 beneficial in the reduction of telegraph flutter in the new facilities on which 

 they were used. 



Remainder of Project: Work started on the manufacture of cable and 

 coils for the New Haven-Providence section of the Boston- Washington 

 project before the Philadelphia- Washington section was completely installed. 

 The section between Hartford and New Haven was placed in service Feb- 

 ruary 13, 1913. Some manufacturing difficulties temporarily stopped 

 cable production, with the result that the Hartford-Providence section did 

 not get into service until October 1913. This installation closed the last 

 gap in the underground cable system between Boston and Washington, and 

 led to the following statement by President Vail in the report to stockhold- 

 ers for the year 1913: 



"During the year 1913 we have made such further advances in the art of loading 

 and balancing underground circuits, and have so greatly improved the interme- 

 diate apparatus, that it is now possible to talk satisfactorily by underground wires 

 from Boston to Washington, in part through types of cable formerly suitable for 

 short haul distances only. These short haul cables make up 47 per cent of the 

 total cable in the line." 



The "intermediate apparatus" referred to were telephone repeaters that 

 had been made available for a few long haul circuits, as mentioned later in 

 the transcontinental repeater development story. In another paragraph 

 of the report. Vail remarked: 



