Answers to your questions:
The "dots" on my drawing indicate the wire had a Morse instrument cut in on it
in the office when it was "open for business" See the "legend" at the center of
the drawing for explanation of the symbols I picked to show this kind of thing....
Where the wire was in the switchboard but had no instrument assigned or was not cut in, the lines
on the drawing simply cross, where the wire took " Terminal Battery" is shown
by a "B", and so on.
As to repeaters, Alamosa didn't have any that I can find out about.
The wires either terminated to Battery at Alamosa W.U.
(FY or AX) office, or went right on through to some other terminal.
I only show one repeater on this drawing and that is on NO. 1 Dispatcher's wire at Durango.
Not certain yet if this was an automatic repeater at the DU (Durango Western Union)
office, or where it was, or even if it was.... The DS No. 1 wire may have gone
on thru to Silverton, and the operator at DG may have manually relayed anything to the Farmington
No. 1 wire...This is one of the little details I haven't cleared up yet.
AS was the railroad relay office at Alamosa, located in the yard office building in later years...It
may have been elsewhere in 1923. DG was the railroad relay/depot office at Durango.
DU was Durango Western Union. That office was a block east and a couple blocks north of
the RR depot in Durango in the last years of WU operation.
FY (sometimes referred to as Ax) was the W.U. Office downtown at Alamosa. RM was the
RR Dispatchers office in the old Alamosa Depot building (still standing)
Most of the information shown on this drawing was taken from old employee timetables
which showed which wire was "cut in" at what station. From examining this information
and from my own experience in working with such circuits (including some of the ones
on this drawing which were still in use in 1965-1973 when I worked on the D&RGW), I can make
some real close determinations as to how things were actually arranged.
For instance, D&RGW wires almost always took terminal battery from the Western
Union office at their end points...Reason for this was, The W.U. built and maintained
all the D&RG pole lines originally, and furnished the instruments thereon. Th RR's part
of the arrangment was to supply the operators to work them. Good deal for both
Companies...The W.U. got open offices in a lot of places they couldn't have afforded
to put them, and the RR got a good, well maintained communications system all over the railroad.
The D&RGW bought all the W.U. plant from W.U. sometime during the 1950's for
a dollar.
Reason for the "loops".
There were two situations...one is where the wire was needed to go up a branch or up a
different route on the railroad, yet needed to be continuous between all offices on the
routes. A Morse Telegraph wire in the W.U. American systems was always a series
circuit from terminal battery at one end to opposite polarity terminal battery at the other end,
single wire, earth return. Standard terminal battery voltage from W.U. was 160 volts D.C.
positive or negative with respect to earth as required for the particular circuit it fed.
A Morse wire can't "branch". There either has to be a repeater at the branching point to connect into
another single wire, or else it has to "loop" up the branch and back.
The drawing shows No. 5 message wire from Denver coming down the valley line and "looping" over to
the division point at Laveta, then back to Alamosa.. this allowed all the stations along both
the Valley line and the LaVeta Pass line to have a common connection to the Denver main D&RG
RR relay office. Pueblo W.U. most likely repeatered this wire at Pueblo, the rest of the
wire distances were perfectly workable without repeaters, if the lines were maintained properly
to minimize leakage to earth along the way (good insulators, no brush or trees in the wires).
Another example of a "loop" is the Santa-Fe "Chili Line" wire No. 01, which apparently looped east of Alamosa to LaVeta as No. 01 and then back to Alamosa as No. 1.
The No. 1 DS wire from Pueblo to Trinidad looped into LaVeta
from the east on a loop from Walsenburg/Cuchara Jct. The timetables show this, and I have some
pole head diagrams that show the same wire number on two different pins on the line in these locations,
That is how a loop was depicted on those portions of the line. LaVeta was a division point, and so
would be working with two sets of dispatchers, one at Alamosa, and one at Pueblo during this time period
Circa 1923.
The other "loops" depicted show a short loop to an office called S1 from a main terminal
office. There was one at Durango, and one at Alamosa.
These were local loops to a telegraph instrument in the Superintendent's office that could
be patched at the switchboard to any wire the Sup't desired to use....handy during derail
ments and that sort of thing.
The other rather unusual loop was on the Pagosa Springs branch. It was a two wire loop
that went from Gato (Pagosa Jct) to Pagosa Springs, and the timetable says "Pagosa Spgs.
Branch loops from Pagosa Jct. and can connect with any wire".
This tells me that Pg could be cut in on any wire going by Pagosa Jct by the operator there
on request...I surmise it stayed on the RR msg wire No. 3 most of the time, but could be
patched into DS wire No. 1 or W.U. wire No. 108 if desired.
Western Union wire No. 118 came fromPueblo W.U. relay office and originally
went down the valley line, thru Alamosa W.U., and up the Creede branch and so provided W.U.
service to all the offices along those routes.
Western Union wire 108 went from Pueblo down to Cuchara Jct, thence westward
through Walsenburg, over LaVeta pass, to Alamsosa, Antonito, Chama, Durango
and eventually ended up terminating in Silverton, and so gave all the offices along those
routes (including Alamosa W.U.) access to the W.U message network.
One other little tidbit of info that has come to light in digging into all this...
Wire numbers originally were all "single or double digits" like 1 , 3, 5, etc.
Some W.U. wires were numbered as "32" . "40" and such. Sometime early in the
20th century, W.U. changed their numbering system and Iron wires changed from
numbering like "3" to "103" "32" became "132" etc. If the wire was a copper wire,
(usually No. 8 AWG hard drawn) the wire number started with a "2"
so W.U. wire No.8 if it was a copper wire became No. "208" and so on.
Exclusive use Railroad wires retained their original numbers, like No. 1, No. 5, etc.
After these changes, it was easier to see which wires were Railroad wires, and which were
W.U. wires on the pole head diagrams... and which of the W.U. wires were copper or iron
by the number they carried. Railroads didn't use copper wire at all until the advent of the
telephone pairs, and then not always for that.
In the timetable information, an asterisk *
showed that the wire was not only in the switchboard at the station but was assigned an instrument and was expected to be cut in during open office hours. The "cross" + symobol indicated the wire was in the swithcboard at that office for testing only, no instrument normally assigned to it.
You can see that No. 109 wire was the main Western Union Thru wire to Durango in the early days, and did not cut in at every office like the way wires and DS wires did. Eventually No 109
and wire No3 were taken out of service and paired and transposed for voice service and used for the RR Dispatcher's telephone circuit. By that time, (circa 1939) Western Union was making use of Leased circuits from the Bell System (Mountain States Tel and Tel in this case) for their through printer wires, like the one from Pueblo to Durango.
