N&W Train Control Questions

[nw-mailing-list at nwhs.org]

I offer the following slate of questions to the N&W List. Some of the answers may be found in the old Annual Reports and some are probably found in the old issues of "Railway Signal Engineer" magazine.  And some of the answers will never be known. (Caveat:  All questions apply only to the "old" N&W, and not those barnacle-like western appendages acquired in 1964.)

1.  Manual Blocking of Trains.  When was the Manual Blocking of trains (as opposed to a "straight Time Table/Train Order" method of operation) first implemented on the N&W?  (My guess would be late 1880s.)  Also, where was the "Manual Blocking" of trains last employed on the N&W, and when?

2.  Track Circuit.  When/where was the first electric track circuit installed on the N&W?  (William Robinson patented the electric track circuit in 1872, and was installing it across the country by 1875.  I'd guess the N&W tried it somewhere in the late 1890s.)  

3.  Interlocking.  When/where was the first interlocking installed on the N&W?   When/where was the last manually controlled (i.e. "rod and pipeline") interlocking closed on the N&W?

4.  Cabins/Towers.  When/where was the first interlocking tower (called a "cabin" in the early days) built on the N&W?  (It may have been "X Tower" at Lynchburg.)  When/where was the last cabin/tower closed on the N&W?  Also, we need to develop a complete listing of all cabins/towers which ever existed on the N&W, with opening/closing dates.

5.  Upper Quadrant Semaphores.  When/where was the first Upper Quadrant Semaphore installed on the N&W?  (My guess would be around 1911-1913.)  When/where was the last one retired, and was it an automatic block signal or a home signal?

6.  Lower Quadrant Semaphores.  When/where was the last Lower Quadrant Semaphore retired on the N&W?  Was it an automatic block signal, a home signal or a train order signal?

7.  Automatic Signals.  When/where did the N&W install the first automatic block signal controlled solely by an electric track circuit?

8.  Rope Pulled Signals.  Where/when was the last rope-pulled or wire-pulled signal on the N&W replaced with pipeline-operated mechanism?

9.  Remotely Controlled Interlockings.  When/where was the first remotely controlled interlocking installed on the N&W?  (It may have been at Bluff, at the east end of the Pepper Low Grade Tunnel, controlled from Cowan.)  Was it operated on a "direct wire" basis, or by "coded impulses"?

10.  Electric Interlockings.  Did the N&W ever have an "all electric" interlocking, or were all its plants "electro-pneumatic" interlockings?  (I'd guess the latter.)

11.  Coded Track Circuits.  When/where was the first coded track circuit used on the N&W?  (I think it was on the Norfolk Division in the mid-1930s.)

12.  "Controlled Manual Block."  Prior to the advent of CTC (Centralized Traffic Control,) did the N&W have any tracks operated on a "Controlled Manual Block" basis?  (I.e. a track signaled for operation in both direction, with levermen electromagnetically precluded from getting opposing signals into the track, by a system requiring "traffic levers" at each end to be in corresponding positions before any proceed signal could be displayed.)

13.  Electro-Pneumatic Switches.  When/where was the first "E.P." or "air switch" used on the N&W?

14.  Traffic Control or "Centralized Traffic Control."  When/where was the first installation of real, code-controlled Traffic Control/Centralized Traffic Control on the N&W?  (I know this question is loaded with semantic pitfalls, as the name "centralized traffic control" was patented and other manufacturers had to get around the patent by applying other names their products employing the same technology.)  Also, we need to develop a chronology covering the installation of CTC on the N&W, which should not be too difficult.

If anyone regularly sees any of the old N&W Train Dispatchers, I'd appreciate them sharing these questions with those gents.

When Ken Miller answers all of these questions, I'll have my next wannabe/wannaknow list ready...

-- abram burnett
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