CONQUEST OF DISTANCE BY WIRE TELEPHONY 345 



9. Phantom working for non-loaded open-wire lines had gotten a good 

 start in the 1904-05 period, in consequence of the standardization of 

 the first satisfactory phantom repeating coil (37-A). The complete 

 commercial exploitation of the phantom circuit, however, awaited 

 the development of usable quadded cable and of phantom group 

 loading. 



10. Several different standard loading systems had been made available 

 for different fields of service on telephone cables, and improved 

 types of cable suitable for use with loading had been developed. In 

 the initial standard loading, the theoretical cut-off frequency was 

 about 2300 cycles. The principal early uses of loaded cable were 

 for circuits between metropolitan city and suburban offices, long 

 entrance cables, and long switching trunks. These installations had 

 yielded large economies by permitting the abandonment of plans for 

 installing sizable networks of these types of circuits in coarse-gauge 

 low capacitance cable, which had been formulated just prior to the 

 invention of loading. A good beginning had been made in the use 

 and in the planning of loading for intercity toll cables, the longest in 

 use being the Boston- Worcester (44 mi.) 1904 cable. Plans for the 

 New York-Philadelphia (90 mi.) and the New York-New Haven (80 

 mi.) loaded cables had been started in 1905. 



11. Substantially continuous efforts to develop a telephone repeater had 

 started inside and outside the Bell System soon after the invention of 

 the telephone. These efforts usually involved receiver-transmitter 

 combinations, and the designation "telephone relay" was quite 

 common. It was not until 1904, however, that there became avail- 

 able a commercially usable result, namely the Shreeve receiver- 

 transmitter type mechanical repeater. This device was being used 

 only on non-loaded open-wire lines, with not more than one repeater 

 in the circuit. Improvements which increased its field of use were 

 worked out later in connection with the transcontinental line de- 

 velopments. 



12. In the reference period, competition by the independent telephone 

 companies was very strong and on the increase, as indicated by the 

 following statistics regarding approximate numbers of stations: 



Ai the end A 1 1 he end 



Item of 1905 of 1907 



Bell Comiecting Companies 246,000 826,000 



Non-Connecting Companies 1 , 596 , 000 2 , 280 , 000 



Independent Co. Totals 1,842,000 3,106,000 



Bell System Stations 2,240,000 3,035,000 



