From 1923 and 1924.

[mrfs42]

*feeling all technologically empowered*

Herewith links to scans [1] of three ancient and fragile Signalling Instructions from the Northern Line Extensions.

Extension from Golders Green to Hendon, 25/9/23:

tinyurl.com/6p9bxl

Reopening to Moorgate and Extension to Camden Town, 5/4/24:

tinyurl.com/67tbc7

Extension from Hendon to Edgware, 1/8/24:

tinyurl.com/698fr7

Enjoy.

Of interest (maybe to TP ) the repeaters are classed as 'orange' not 'yellow', but thankfully not 'amber'. ;D

I think that some signals could work as draw-ups at Camden - seems to be a means where the motorman could lean out of the window and pull a rope, which would prove that he was at a stand and therefore could approach the nxt signal, protecting the junction at reduced speed. Read it and see what you think....

[1] The joys of gaining an A3 scanner and discovering Photoshop in matter of hours!

[tubeprune]

This is fascinating stuff mrfs42. If you have better images so I could read the signal numbers, please pm me. The rope pull is an interesting feature. I never heard of it before.

The plungers are interesting too. I saw these in New York on the subway. They have some very complex underground junctions there and they have plungers labelled "Bridge" or "Tunnel" for example so the motorman (they still can them motorman there) can select the route he is supposed to take. One is for the Brooklyn Bridge, the other for the tunnel under the East River.

As for the "orange", JPT should have known better.

[yerkes]

I see that the signalling diagram was produced by the "Signal Engineers' Office, Earl's Court Station." Did that become the office for the entire combine from 1933, or did it only last as long as the Underground Group?

[mrfs42]

I'm fairly sure the Engineers Office stayed at Earls Court until the Department of the Chief Signal Engineer was created - think this was in Major Morkills time (when Dell was a mere youth) - and the department moved out to Bollo Lane in Acton.

[Tom]

ISTR the move to Acton was around 1965.

Wasn't Major Morkill the Met Signal Engineer? The District's (and I believe, the LER, via the common ownership) was W.S. Every.

And another odd point... the Hendon Plan has a signals drawing number in the corner (BS.2707). According to the big book of numbers I have access to, 2707 was a 'C' size drawing which was cancelled and never used!

[mrfs42]

I think so - however the situation was slightly complex insofar as there was some degree of overlap between Every and Morkill. UERL/LER and very early LPTB patents from the early 30s were issued by Every and Dell.

I can't honestly remember at the moment, as away from the library. I've a feeling Morkill died in harness, just before the LPTB formation.

Edit: Have you noticed the pencil corrections and renumbering on the Hendon sketch (approaches to Brent) - this might explain why the drawing doesn't historically exist.

[mrfs42]

May 19, 2008 14:24:40 GMT tubeprune said:

This is fascinating stuff mrfs42. If you have better images so I could read the signal numbers, please pm me. The rope pull is an interesting feature. I never heard of it before.

A further scintilla of detail from the February 1926 UndergrounD group Appendix to the Working Timetable:

157 - "Calling-On" Signals

The plunging pole or rope operated by the Driver gives an indication to the Signalman who will, on receiving the information, lower the home signal or 'calling-on' signal as may be necessary. Drivers pulled up at the home signal should, therefore, at once operate the plunger, in order to advise the Signalman that their train is stopped at the signal.

Plunging poles should be pushed gently but firmly, and held forward for a few seconds. They should not be jerked, or operated before the train is brought to a stand.

The Signalman must not operate the lever controlling the 'calling-on' signal until he has satisfied himself that the train is in a proper position in the platform for coupling and that the respective tracks have 'cleared' or 'broken down' as the case may be.

Also (from the 1926 Appendix too):

161 - Home Signals Nos 4A and 4B, Camden Town Junction

When signals E, 4A and 4B are at Danger the Drivers of 6 and 7-car trains must draw their trains close up to them, otherwise the track in the rear will be broken down , and the following train will be delayed.

Of interest, the term 'Driver' seems to be used in preference to 'Motorman' - I've noticed elsewhere in the publication that 'squeegee' is used as a verb (a very early use of this term I think).

I understand the use of the term 'broken down' as it is used in other signalling firms' publicity of a similar era. It does not refer to a bust bit of rail but the broken contacts when the track relay arm drops down.