Etrump Wrote:
-------------------------------------------------------
> SouthPark and I have been discussing this a
> little...
>
> Seems the Western Union did most of that kind of
> "modernizing"
> in the late teens-early '20's during line rebuilds
> and upgrades.
>
> Probably went on for a decade or two before
> largely completed all over.
>
> The "birdhouse" cable box was placed high above
> the top arm and the bridle wires were run from the
> breakirons up into it thru insulated bushings in
> the sides. They then connected to the Depot cable
> at a terminal block mounted in the box. Fuses and
> arrestors were not mounted in the pole-top depot
> cable boxes...those were placed inside at the
> switchboard.
>
> The birdhouses eliminated the obvious easy path
> for lightning to enter the depot buildings that
> existed with the open wire downleads to building
> mounted "crossarm and pin" entrances.
>
Google Books has "Official Diagrams of the Postal Telegraph Co." for 1906; cable pole boxes are discussed as well as plans for same. So, they have been around quite a while.
Skip Luke
Switchman (ret): Grand Canyon Railway;
Engineer (ret): Georgetown Loop RR Inc., Sumpter Valley Ry., Monticello & Sangamon Valley;
Dispatcher(ret): Illinois Central, White Pass & Yukon, Burlington Northern Ry.
Mariner, Musician, Miner