N&W in 1912--Wires

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Another great post, Gordon !  I had always wondered when the N&W replaced the old iron wire with copper. 



I know of no source for   systematic information about the conversion from iron to copper, but one does pick up incidental bits about the subject here and there .  Robert Luther Thompson's work, "W iring A Continent - The History of the Telegraph Industry in the United States 1832-1866" (Princeton University Press, 1947) is oriented toward the commercial side of the telegraph business, but does contain some references to the iron/copper debate in the early days.  Based on information given by Thompson, it appears that as early as about 1857 (thirteen years after the invention of the telegraph,) the telegraph companies were beginning to use copper in some situations.  It would be interesting to know when the railroad companies started making the transition. 



Re lative advantages: 



1.  Iron was (and still is) much cheaper than copper. 



2.  Copper has a much lower resistance (ohms per mile) than iron, and therefore consumed somewhere around half or two-thirds less current for operation.  Remember, in the old days  electric voltage was  derived from "made batteries."  Each cell was made in a glass jar, from  a piece of zinc, a piece of copper, and acid, and each cell yielded around 1.25 to 1.4  volts.  If you needed 6 volts, you made four or five battery cells and seriesed them.  So "generating electricity" was a very expensive proposition back  before the invention of the dynamo, the rectifier and the storage battery . 



After  Western Union and the railroads began the conversion from iron to copper wire, they found that a pole line built with copper wire was a lot more resilient than a pole line built with iron wire.  In heavy ice and snow storms, the old iron wires would break, but the copper wires would stretch and sag and stay in tact. 



I also heard some of the old railroad telegraphers (men who were working in the early 1920s,) remark about the better operating characteristics of telegraph circuits over copper wire via-a-vis iron wire. 



Three decades   ago I was hi-railing the old Erie Main Line west of Hornell, NY, and saw some old iron wire still up on the poles near Andover .  A piece just ha d to come home with me, but the dern stuff was so hard that I could not cut it with a very large set of lineman's pliers.  However, when flexed just a couple times, the old iron wire broke easily.  It had been  badly, badly corroded, by both water and the sulphu rous blast from the stacks of a million passing steam engines.  (I now have that chuck of iron wire in my telegraph office, strung between two insulators taken from  the same pole, and there is now an operating Morse telegraph circuit running over that chunk of wire ! ) 



Keep digigng, Gordon!  You come up with some real winners... 



-- abram burnett 

 
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