6 BELL SYSTEM TECHNICAL JOURNAL 



of materials and providing interchangeability both of materials and 

 working forces and is very important in making possible the operation 

 of the entire interconnected network as a single system with uniform 

 grades of service. 



As has been stated by Mr. Gifford, President of the American 

 Telephone and Telegraph Company, "The ideal and aim today of 

 the American Telephone and Telegraph Company and its Associated 

 Companies is a telephone service for the nation, free, so far as humanly 

 possible, from imperfections, errors, or delays, and enabling at all 

 times any one anywhere to pick up a telephone and talk to any one 

 else anywhere else, clearly, quickly and at a reasonable cost." With 

 this aim in view, continuous effort is made further to improve and 

 to extend the service within the nation and also the telephonic con- 

 nections to other nations. It is recognized also that changes in 

 business and social conditions bring about repeated changes in the 

 services desired by the people of the nation and in the character and 

 appearance of facilities furnished to them. These facts, in addition 

 to the onward march of the application of science, form an important 

 basis for the continued study by the general staff of the development 

 of all phases of the telephone system. 



A few figures relative to the size and growth of the Bell System 

 are helpful in an understanding of the more specific telephone prob- 

 lems which are discussed below. Such figures are included in the 

 statistical summary appended to this paper and include data regarding 

 telephone messages, numbers of telephones, miles of wire and amount 

 of telephone plant. 



In accordance with the general organization of the Bell System, 

 the engineering problems involved in the design, construction and 

 maintenance of the plant of each operating telephone company are 

 the responsibility of the engineering department of that company. 

 General studies of methods of improvement of service and the devel- 

 opment of new apparatus and systems of communication, together 

 with consulting engineering advice, are provided by the general de- 

 partments. 



For the provision of new plant to meet additional demands for 

 service, in the case of the more important items, often one year, and 

 sometimes more, is required between the completion of detailed engi- 

 neering plans and completion of construction. Furthermore, to ob- 

 tain maximum economy it is necessary that much of the new construc- 

 tion provide for expected increases in demands for service for a number 

 of years to come. This applies particularly to telephone buildings 

 and to runs of underground conduit and to a lesser extent to cables, 



