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BELL SYSTEM TECHNICAL JOURNAL 



requirements for circuits are very heavy and in addition, as is well- 

 known, the topography of the country is such that the through routes 

 which can economically be used for pole lines are limited. At present, 

 these few routes are fully occupied by the pole lines of the various 

 utilities and included in these lines are three fully loaded telephone 

 trunk lines. Another item of importance in the consideration of 

 aerial wire construction is the very severe damage frequently experi- 

 enced in many sections of the country on heavy aerial wire lines 

 from ice and wind storms. Even lines built with exceptional strength 

 fail in these storms and the interruptions to service are serious mat- 

 ters to the users as well as to the telephone companies. The restora- 



Fig. 3 — Damage to Section of New York-Boston Main Line Near Worcester, Mass. 

 Storm of November 28, 1921 



tion costs under the conditions that naturally exist at such times are 

 abnormally high. 



Figs. 3 and 4 show the effects at one point of the ice and wind storm 

 in New England on November 28, 1921, and are proof that this 

 problem is real. This particular spot is near Worcester, Mass., and 

 the line is a section of one of the principal aerial wire routes between 

 New York and Boston. In this storm, many thousands of poles 

 were broken and even where a few poles remained standing due to 

 specially strong construction, the load of ice combined with the wind 

 was too great for the wires to withstand. There is therefore a prac- 

 tical limit to the number of wires that can be safely and economically 

 carried on a pole line. 



Where the practicable routes for pole lines are limited, where the 



