[GreenKeys] Copper Wire?

[Douglas W. Jones]

On Aug 31, 2007, at 10:51 AM, telegrapher at att.net wrote:

> Copperclad steel was used for the telephone lines in the early years.

I helped clean up the right-of-way of the old Burlington Cedar Rapids
and Northern railroad -- later part of the Rock Island system, when,
post abandonment, parts of that right of way became the Hoover Nature
Trail.  All of the trackside signal and telephone lines were copper
clad steel wire.  No recycler will take the stuff.  It's near immortal,
looks like copper wire unless you know better, and has a pretty stunning
tensile strength.

Of far more interest, to me, was when we found the occasional trackside
relay box or signal that had been missed by the scrappers.  The relays
and signal mechanisms are fascinating examples of extraordinarily
rugged, fault tolerant designs.  No springs allowed, all relays operate
by gravity (springs rust, gravity is extraordinarily reliable).  Relay
contacts were huge silver lumps, and the basic 3-aspect block
signalling track circuit is really nice because every possible
failure of the circuit has been anticipated and every one of them
leads to a signal aspect that is interpreted as stop (and then
proceed with caution).

		Doug Jones
		jones at cs.uiowa.edu