Aberdeen Railway (Drumlithie)

[Colin Wells]

On a Caledonian Railway signal diagram for Drumlithie dated February 1919 - in what I understand to be a double line area from research including the historical Ordnance Survey 25" map - the Aberdeen end of the diagram is depicted as a double line coloured blue (in a similar format to the example on the main signal box website "Taynuilt", with blue main line and brown sidings) whereas the Perth end has the two (otherwise "main") lines one blue line with blue crossover, the other brown with the addition of a trap point and ground signal, plus a parallel (brown) siding with its own trap and ground signal. This is a bit of a puzzle, at least to me, given that the railway appears to have been double line. Has anyone any ideas about this? If one line was worked as a long siding I would suggest the Great War could have brought some special arrangements; and although the diagram date is several months after the Armistice, apparently that was a long drawn out affair before peace was officially ratified in January 1920.


Photo: Colin Wells

[Signal-sighter]

Unfortunately the photo isn't displaying here.

Now restored - JH

[Corrour]

Hi Colin,

I have drawings showing several versions of the Drumlithie layout from around that era, including two slightly different versions of the 1919 SBD drawn by the late Forbes Alexander. In all diagrams the track is double, though indeed there is a siding at Perth end on Down Line. I can comment better when I see the drawing posted.

kind regards,

Robert

[Chris Osment]

Well, I don't know the location, but the Perth end of 22 appears to have an FPL 23, which would suggest IMHO that the 'blue' line towards Perth was bi-directional - in other words, only single-line rather than double-track.

[davidwoodcock]

Was the line towards Perth singled during the Great War (probably in 1917) in order to release rail and sleepers to the War Department for use in one of the various war zones? I believe that there were a number of examples of this happening and, indeed, one line not too far away was removed in its entirety (and IIRC never reinstated).

[Colin Wells]

Another possible clue to altered working - the distant signals at either end are "fixed at danger" and the diagram shows the two most likely levers for them, 7 and 17, as spare.

[aberbrothock]

The main line to Aberdeen doesn't seem a likely place to take up track to send to the Western Front. But there is a substantial viaduct between Drumlithie and Fordoun, the next block post south, over the Bervie Water. These viaducts were originally built of timber in the 1860s and by 1918, with heavier traffic, they were life-expired.

Sure enough,Google finds the following plan in the National Records of Scotland:

RHP128756-128758: Three hand coloured contract drawings showing elevations, plans sections and details for renewal of bridge over Bervie Water between Fordoun and Drumlithie (Caledonian Railway): 1918 annotated with the signatories to the contract 14 April 1919

So my guess is a period of single-line working while the viaduct was renewed.

Great to see such a nice example of a Caley diagram. Thank you for posting it.

Graham

[aberbrothock]

The idea of viaduct renewals triggered a vague memory ... sure enough, in my trusty Alexander & Nicoll "Register of Scottish Signaboxes", there is mention of "Ballathie Viaduct Temporary" signalbox (between Perth and Forfar) from October 1918 to January 1920. So there must have been quite a bit of disruption to schedules on the Strathmore line.

[Corrour]

Colin is the diagram you posted the original?

kind regards,

Robert

[Colin Wells]

Original? - indeed it is. Many thanks for the interest and information.

[Corrour]

Interesting as the late Forbes Alexanders drawing shows the Up tracks transposed....possibly due to working on each track i.e. two diagrams during the 'extended possession'?

[Signal-sighter]

Very, very interesting. I'm intrigued that the diagram shows Aberdeen and Perth rather than Carmont and Fordoun. Was this common Caley practice?

[Corrour]

Hi yes it was common Caley practice to show the major centres rather than block post on each side.

kind regards,

Robert

[Colin Wells]

Usually an obstruction or repairs to the line would call for working by Pilotman but in this instance work on a bridge would no doubt be of several months' duration. The diagram indicates that the arrangement was more permanent than Pilotman working, given the locking 23 for points 22 and the trap 24 as well as the ground signal 25, and the possibility that home signal 16 might have been worked for the wrong line. Perhaps that suggests the installation of temporary token machines or was an alternative method of one train working along the single line available for this kind of arrangement in 1919?

[Mike Hodgson]

This explanation certainly sounds plausible from a signalling point of view but would it really be practicable to renew one side of a timber bridge whilst keeping the opposite line safely open to traffic? There may not have been much consideration over Health & Safety of the workforce back then, but surely there would be some concern over the risk that the works would undermine or otherwise foul the line still in use? I don't know the location - were they two separate but parallel viaducts?