IIXGINEERIXG I'ROHI.liMS Ol- THE PEI.I. SYSTEM 317 



In iln' earliest clays of the telcphiine serxice, the problem of l.iyiiisj 

 out a telephone plant was a simple one. A \er\' small switchhoard, 

 simple in rharaeter ami casih' moxetl, if necessary, was plaritl in 

 some convenient location, usualK' in rented ((iiarters, and from that 

 switchboard wires were run one by one as nee<le<l, to the premises^ af 

 those desiring sH.'rvicc, either on poles or over house-tops. I'nder such 

 simple and ruilimentar\' conditions, no serious question of the future 

 nei-iled to be answered. Tfxlay, how^ different is the telephone situa- 

 tion in many large cities, such as Chicago, or throughout the system. 

 L.irjje and specially designetl buildings must be constructed for the 

 accommodation of the necessary interconnecting or .switching mecha- 

 nisms; expensive switchboards must be placed in these buildings; 

 conduits must be extendetl from each f>f these buildings along appro- 

 pri.ite routes to reach the thousands of telephones which receive ser\'ice 

 fro 11 these switchboards; other conduits must be placed between these 

 switchboards and the other buildings and switchboards throughout 

 the city so as to provide the means of intercommunication between 

 the subscribers connected with the switchboards located in different 

 In.ildings; still other conduits and cables must be placetl between these 

 switchboards and the central switchboard or toll board from which 

 radiate cables and conduits and lines extending to the suburban area, 

 to adjacent cities, to all the other principal cities in the United States, 

 and to Canada. 



Each of the buildings must be placed in some definite location and 

 it is necessary to plan this well in ad\ance and to direct the growth 

 of the plant toward that location, even though the building may not 

 be built for some years hence. Otherwise, very serious and costly 

 rearrangements of plant would be necessary at the time the office is 

 opened. Furthermore, each building must be planned for some defi- 

 nite ultimate size, although, of course, the whole building need not be 

 built at one time. Ducts cannot be placed under the streets one by 

 one as needed. Public sentiment would not, of course, tolerate the 

 opening of imp>ortant street routes several times, or even once, each 

 year for the purpose of placing an additional duct. Neither would it 

 he economical, if practicable, to construct conduits in this piecemeal 

 way. The manholes in these conduits must be planned with reference 

 to the number of ducts extending into them, not only the ducts initially 

 placed, but if side runs are to be made from these manholes or if other 

 ducts are to be placed later, this fact must be foreseen and provided 

 for, or extensive and expensive alterations are ine\itable at a later date. 



I might go on and multiply the conditions which must be met in 

 constructing telephone pl.int in a conntr\' such as onrs in which not 



