Vera Jct and "Medium"
NW Mailing List
nw-mailing-list at nwhs.org
Tue Jun 24 13:56:40 EDT 2025
Jim,
With apologies, I'll attempt a reply to your original post with some
specifics.
Diverging indications notify an engine crew of a speed restriction due
to one or more turnouts ahead. By 1951, anyway, N&W Operating Rule 105
(b) simply stated that unless otherwise provided, speed is restricted to
25MPH for passenger trains and 15MPH for other trains or engines when
using turnouts or crossovers. As Jimmy stated, exceptions were noted in
ETTs and could vary a lot, for example, between the Radford and
Pocahontas Divisions.
So, diverging aspects are applied to signals in both directions
"through" the turnout's slower/secondary route. BTW, the N&W's CPL
version is not included in the earlier Rule 283 examples below. The
three diverging indications are shown here, starting with the
distant/advance signal indication Approach Diverging:
This is an eastbound at Vera Jct. on the Cincinnati line approaching the
turnout on the eastbound main from Columbus, shown in the lower-right
corner. I can't recall specifics as to what other signals are here
(bi-directional? both directions? etc.) in this time frame and with
which aspects.
So, what's with the term "medium" and the N&W?
I don't know. I've asked around, and this came up here on the List
several years ago. As of 1951, it appeared in two contexts within N&W
signal rules:
In the signal indication description of Rule 285 – Approach, the term
"medium speed" appeared: "Proceed preparing to stop at next signal.
Train exceeding medium speed must at once reduce to that speed." It
appeared in the Operating Rules Definitions as half the max authorized
speed, but not to exceed 30MPH.
In the name of the three "diverging" indication rules, "medium" replaced
"diverging," e.g., Diverging Clear became Medium Clear. However, the
term "prescribed speed" was used in the rule descriptions per Rule 105
(b) above – not medium speed.
Neither usage appeared to have much, if any, direct relevance, and the
ambiguity seemed to be acknowledged later, because by the 1981 Rule
Book, both instances were deleted. "Medium" was changed back to
"Diverging" for indication names, and the reference to "medium speed"
was removed from the Approach Rule description and the term was removed
from the Rules Definitions.
Hope this helps, just my take; edits, thoughts and questions welcome.
Grant Carpenter
On 6/19/2025 7:55 AM, NW Mailing List wrote:
> All signal fans,
> I just found this definition/explanation for what a "diverging" route
> can be interpreted to be and it covers the case at Vera:
> One of these days I hope to understand to signal a railroad.
> Jim Cochran
>
> On Wed, Jun 18, 2025 at 8:47 PM NW Mailing List
> <nw-mailing-list at nwhs.org> wrote:
>
> The operating book rules calls out the AAR rules in my '51 and '45
> rule book. That is speed signaling, although if you look at the
> rules as written they do a bad job explaining that. The only thing
> that usually drove medium speed was a diverging route in a turnout.
>
> Is there another facing point turnout ahead?
>
> David Baker
>
> On Wed, Jun 18, 2025, 6:44 PM NW Mailing List
> <nw-mailing-list at nwhs.org> wrote:
>
> Grant,
> Thanks for the reply and great seeing you at the con as well.
> Your answer caused me to dig more deeply into the history of
> N&W aspects/indications and in particular the horizontal arm
> over vertical arm aspect that has most recently been referred
> to as "diverging clear". Please refer to the attached pages
> from N&W rule books as reference for what follows.
>
> In 1910 it was called "slower speed route clear" when used in
> conjunction with one high speed route and diverging routes.
> Seems clear this was speed signaling.
>
> In 1915 it was "proceed under control, being prepared to stop".
>
> In 1930 it was just "proceed". Does anyone have a copy of the
> rules between 1915 and 1930? I'd like to know what that one
> has to say.
>
> In 1945 it was " proceed through diverging route at prescribed
> speed". This looks like route signaling. Again if someone
> has intervening information, I'd appreciate knowing about it.
>
> In 1951 it was " proceed through turnout route at prescribed
> speed" which would seem to indicate route signaling, but the
> aspect name is "medium clear" which point toward speed signaling.
>
> In 1961 it was the same but showed the option of a colorized
> aspect.
>
> As far as I know this was maintained until the end of the
> N&W. The term through diverging or turnout route seems to
> reinforce my questioning its use where one line "joins"
> another. When I visited Tom Dressler many years ago, he
> informed me that going "through" a turnout was to take the
> diverging path while going "over" a turnout meant staying on
> the non-diverging route. Both of these would indicate a
> facing points movement and wouldn't seem to be readily
> applicable to trailing points movements.
>
> The NORAC definition of this aspect is something like proceed
> at medium speed until you train clears turnouts or
> interlockings and then proceed at prescribed speed. This
> would seem appropriate for such a situation as we find at
> Vera, but I have not seen this kink of definition in any
> reference for N&W signaling.
>
> Hope there may be more to the story and would welcome input
> from anyone who has experience/knowledge of how N&W signaling
> worked and the philosophy used by the system designers.
> Thanks,
> Jim Cochran
>
> On Tue, Jun 17, 2025 at 7:47 PM NW Mailing List
> <nw-mailing-list at nwhs.org> wrote:
>
> Jim,
>
> Generally. . .
>
> Route signaling is speed signaling by implication.
>
> So, diverging aspects can indicate a lower speed through
> the diverging route of a turnout, compared to the adjacent
> track speed, and regardless of direction.
>
> So, diverging aspects will be used when facing points, and
> may be used when trailing points.
>
> . . . mostly.
>
> Good to see you and All at the Convention.
>
> Grant Carpenter
>
> On 6/8/2025 10:31 AM, NW Mailing List wrote:
>> Attached is a photo of Vera Jct. showing the signal
>> facing Peavine traffic. Why would the "main stem" from
>> Columbus have been considered a "diverging" route in this
>> case? Perhaps it is in some way analogous to middle
>> sidings being signaled for diverging aspects where they
>> rejoin the main. I tend to think of diverging aspects
>> being displayed to facing points movements where they are
>> signaled to take a route that "diverges" from the one
>> they are currently on. Of course there are no "joining"
>> aspects, so did the term "diverging" cover the act of
>> taking a route that your current route is joining? Any
>> thoughts will be appreciated.
>> Jim Cochran
>
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