Philadelphia-Pittsburgh Section of the 

 New York- Chicago Cable' 



By JAMES J. PILLIOD 



Synopsis: Engineering and construction features involved in a complete 

 telephone cable system over 300 miles in length and connecting Philadelphia 

 and Pittsburgh, Pa., are described in the following paper. This cable is 

 designed to operate as an extension of the Boston-Washington under- 

 ground cable system with which it connects at Philadelphia. It is also 

 designed for operation in connection with the Pittsburgh-Chicago cable 

 now under construction, and other cable projects included in a compre- 

 hensive fundarnpntal plan. 



Beginning with the fundamental factor of public requirements for com- 

 munication service between cities separated by various distances, there are 

 next considered the methods available to provide this service. Small- 

 gage, quadded, aerial cable, which was decided upon for use in this section 

 after careful economic studies, is described in a general way and the im- 

 portant advantages of the application of loading and telephone repeaters are 

 outlined. The use, in connection with this cable, of the recently developed 

 metallic telegraph system for cables is referred to and some facts are given 

 regarding power plants, test boards and buildings. A few of the many 

 possible combinations of cable and equipment facilities into complete 

 telephone circuits, which will furnish the service required as economically 

 as now possible, are illustrated. 



The necessity of complete coordination of the many factors involved 

 in a project of this kind is emphasized. 



Introduction 



THE placing in service in the latter part of 1921 of the final section 

 of a continuous telephone cable over 300 miles in length between 

 Philadelphia and Pittsburgh marked a new point of achievement 

 in the steady development and construction of facilities designed 

 to render to the public the best possible long-distance telephone 

 service. Furthermore, this cable forms an important part of a com- 

 prehensive plan of long-distance cable construction throughout that 

 section of the United States lying in general east of the Mississippi 

 River and north of the Ohio and Potomac Rivers. 



In the discussion of a project of this kind which involves many new 

 practices and the expenditure of several millions of dollars and which, 

 with related work already completed, forms the groundwork for 

 large expenditures in the future, it is usual to inquire first into the 

 underlying reasons for carrying out the project and then into the 

 methods adopted. In the following discussion an endeavor will 

 therefore be made to furnish some information on these two items 

 in their relation to the Philadelphia-Pittsburgh cable, although, as 

 will be obvious, the many different points can be covered in only 



' Presented at a meeting of the Philadelphia Section of the A. I. E. E., January 9, 

 1922, presented at the Annual Convention of the A. I. E. E., Niagara Falls, Ont., 

 June 26-30, 1922, and appearing in the Journal of the A. I. E. E. for August, 1922. 



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