THE DEVELOPMENT OF TELEPHONE SYSTEM 519 



the pioneer telephone days, just as now happens thirty years later. 

 The prevailing belief among the early telephone men was that iron 

 wire would have an average life of from fifteen to twenty years. But 

 it only required a brief experience to show that many iron circuits on 

 city pole lines, even of extra best (E. B. B.), had an average life of 

 less than four years, and that rapid rusting rendered some circuits 

 worthless within three years. 



For pole lines, chestnut was the principal wood used in 1876, 

 though there were also many white and some red cedar poles used, and 

 here and there a few locust and oak poles were occasionally utilized. 

 The number of poles then placed to the mile varied according to the 

 climate and the breadth of view of the owner. Ordinarily they 

 ranged from fifteen to forty, the average in the northern states being 

 from twenty-five to thirty, according to the downward range in tem- 

 perature. As a rule, poles 25 feet in length answered every purpose, 

 for there were no other lines to interfere, while 4-inch or 5-inch tops 

 offered sufficient support to carry the few wires required in 1878-80. 



Now-a-days the approved practise in building telephone trunk 

 lines is to require selected heavy chestnut or cedar poles, not less than 

 eight inches in diameter at the top, and with a corresponding heavy 

 butt, and in length ranging from thirty to fifty feet, depending on the 

 contour of the country and the number of circuits to be carried. From 

 forty-four to fifty of these poles are placed per mile, while the depth 

 that they are set in the ground ranges from five feet to nine feet, 

 depending on the length of the pole and the character of the soil 

 or rock. 



It may be recalled that in the first circular issued by 'the pro- 

 prietors of the telephone,' dated Cambridge, Mass., May, 1877, Gardiner 

 G. Hubbard stated that 



telegraph lines will be constructed by the proprietors, if desired. The price will 

 vary from $100 to $150 a mile; any good mechanic can construct a line; No. 9 

 wire costs 8% cents a pound, 320 pounds to the mile; 34 insulators at 25 cents 

 each; the price of poles and setting varies in every locality; stringing wire $5 

 per mile; sundries, $10 per mile. 



At the first glance the amount of material shown in that estimate 

 may appear somewhat inadequate, judged by modern methods of stan- 

 dard pole line construction, calling for forty-four poles to the mile. 

 Yet a moment's study will show that the proposed line was substantially 

 planned, was far stronger and would probably possess far better talking 

 qualities than some present day private lines. In an elaborate cata- 

 logue issued by a manufacturing telephone company in 1906, twenty- 

 nine years after Mr. Hubbard's circular was issued, the following 

 estimate appears : 



To give something of an idea of the expense of building one mile of line, 

 grounded circuit (1 wire), we submit the following items. We do not estimate 



