The LNER Encyclopedia

If you take a look at the well known photo of Empire of India at Potters Bar, it features and early colour light signal:

This links to the photo in question.

Can someone who is knowledgeable in these matters tell me:

1) What might it be above the three aspect colour light head, almost totally cropped out of the photo (looks like another signal head)
2)What would the white? light below the main signal head indicate?
3)What is the sign with the horizontal bar below that for?

I spent so much time looking at the detail of the coaches in that shot.. now the rest of it has piqued my interest!

Cheers

Jukebox

I am not sure if there was another aspect over the three aspect in the photo but I doubt it. It was a popular spot for photographers so we should be able to check it out.

The item below which you thought was a white light is in fact a Rule 55 plate advising that the fireman should alight and call in if at danger.

The other plate with a horizontal black stripe denotes an automatic signal.

2512silverfox wrote:I am not sure if there was another aspect over the three aspect in the photo but I doubt it. It was a popular spot for photographers so we should be able to check it out.

The item below which you thought was a white light is in fact a Rule 55 plate advising that the fireman should alight and call in if at danger.

The other plate with a horizontal black stripe denotes an automatic signal.

Thanks very much for that explanation. Interestingly, when I looked at my copy of that book at home, it does not have the shadow above the main light head.

Looking at that photo, and this page - easier to find once you know what to Google for - I agree it is a Rule 55 plate/D-sign, but for my eyes, I see a lens and hood in that picture, not just a plan plate.

No matter - I am more educated now than I was when I first asked the question!

Cheers.

The Potters Bar box diagram showed D11 signal (located in the area known as Ganwick) merely as a simple 3-lens multiple-aspect signal with 'Auto' plate, so I very much doubt there was any other signal unit above the 3-aspect one.

I think the 'D'-plate might be better regarded as meaning that there was some means at the signal for Rule 55-reminding the signalman, as I've a feeling that they were also sometimes fitted where there was an FCB ('Fireman's Call Box'/plunger). However, I've a hunch that FCBs were uncommon on the LNER, at least around the southern end of the ex-GN Main line anyway.
I know of a diagram for (but not from) Greenwood box for 1932 (when the colour-light signalling here was installed) [ http://www.signalbox.org/diagrams.php?id=335 ] which has the equivalent Up line signal here, U12, with a 'D'-sign and an adjacent telephone symbol.
And at the time of the late 1950s New Barnet (Greenwood box) - Potters Bar quadrupling, it seems to have still been practice that a 'D'-sign was certainly used if there was a telephone to the signalman, as was the case at New Barnet North box's new C/L Up home signals (606 yards from the box).

Just to close this one out, I've checked a larger version of that photo in another LNER volume, and Silverfox is correct, it is just a three aspect colour light. No idea why that image I linked to appears to have an addition above it.

Before this goes to bed let me add this diagram the features D11..

http://www.flickr.com/photos/32297024@N ... hotostream

D11 is shown as a splitting distant for Potters Bar. Is it possible it may have been configured differently at some stage?

Here is an earlier control panel from Potters Bar. This slightly pre-dates the Greenwood diagram as the down slow is not a through road.

http://www.flickr.com/photos/32297024@N ... hotostream

The arrangements during these stageworks were quite fluid and not very well recorded.

Just an observation. I was always under the impression that the Eastern (and maybe from the LNER) used U & D Prefixs for automatric signals on the Up and Down lines respectively and I think, but am less sure, that the number related to the route mileages. It about fits with Greenwood shown in this thread.

cambois wrote:Just an observation. I was always under the impression that the Eastern (and maybe from the LNER) used U & D Prefixs for automatric signals on the Up and Down lines respectively and I think, but am less sure, that the number related to the route mileages. It about fits with Greenwood shown in this thread.

I'm sure you are correct regarding this location. New Barnet station was pretty closely by the 9 MilePost, so I'd reckon the 10 MP would've been around Greenwood box somewhere. The principle was that the Auto signals were numbered according to the last MP number passed in the direction of travel, which is why D11 is just north of U12.

R. pike wrote:Before this goes to bed let me add this diagram the features D11..

http://www.flickr.com/photos/32297024@N ... hotostream

D11 is shown as a splitting distant for Potters Bar. Is it possible it may have been configured differently at some stage?

Here is an earlier control panel from Potters Bar. This slightly pre-dates the Greenwood diagram as the down slow is not a through road.

http://www.flickr.com/photos/32297024@N ... hotostream

The arrangements during these stageworks were quite fluid and not very well recorded.

Very interesting R.P. I'd never noticed that form of D11 before, but it seems very logical.

You're definitely right that that Greenwood diagram is a late one; hence the oddly-configured split of the Up Main into the Up Slow and Up Fast on the right, which was a temporary arrangement during stageworks of changing from the old 2-track layout north of Greenwood to the new 1959 quadrupling throughout.
This means that at the time of this diagram, Potters Bar power box was already open, having the layout as per your 'old panel' photo, with first controlled Down signal being PB4 outside the north end of Potters Bar Tunnel (the approximate location of the pre-1930s Mimms signal box).

In the old Potters Bar layout, the two roads only opened out to four at the north end of the station, at which time D12, at Mimms, was an LNER Auto Stop/splitting Distant-type signal, with a main 3-aspect head and two small distant ones below; the same arrangement as U12 on the Greenwood diagram.

With the Potters Bar Tunnel (exclusive) section through the cutting to the station quadrupled, PB4 signal as you can see, governed the new Down road divergence from one into two tracks, so it makes sense that the preceding signal, the previously simple 3-aspect Auto D11 of old, had then newly changed to also act as a splitting distant for PB4, and was of the much more modern, twin-main head configuration, you may note : I see it had also become a 4-aspect signal instead of 3.