Narrow Gauge Signalling

[ge_rik]

Here's a pic of Southwold station throat that may help - you can see the y-shaped yokes from the point blades to the signal hand levers.



These are combined 'block' semaphores and point indicators, I think.  This appelation does not universally apply, but I would a) need to look at the 1908 signalling regulations carefully and b) check to see if there were more than one centrally or only at one end of the loops.

Interesting. It looks as if they moved the signals between the two photos. In the one above, the 'inner' is beside the turnout to the carriage shed. I my later one the inner is by the leading turnout for the station.

Rik

[Andrew]

Here's Aberystwyth, two versions.  As you can see the concept of an overlap under Regulation 4 is a bit nebulous.

Why thank you! You are a remarkable chap MdeC...

I know it's not the point (with or without FPLs), but I'm enjoying the font. Is it the 50s BR one, or the London Underground one, or another Sans Serif affair that just happens to have a nostalgic vibe?

Cheers,

Andrew.

[Marquis DeCarabas]

Interesting. It looks as if they moved the signals between the two photos. In the one above, the 'inner' is beside the turnout to the carriage shed. I my later one the inner is by the leading turnout for the station.

OTTOMH, I don't think anything changed at Southwold, but I will dig around. I've found some of my virtual notes on one level of this machine, but I need to dig a bit deeper as I think there are more notes on the preserved desktop of the next further machine back in time.

Why thank you! You are a remarkable chap MdeC...

you are too kind. but as a bonus, I offer another drawing at the end which has commonalities with the Southwold arrangements.

I know it's not the point (with or without FPLs), but I'm enjoying the font. Is it the 50s BR one, or the London Underground one, or another Sans Serif affair that just happens to have a nostalgic vibe?

It is the LPTB one. Much nicer than 50s Gill Sans and more adaptable. Though the signature sigil is *not* an UndergrounD roundel, I wonder if anyone can guess the origin of the symbol?

Anyway - enjoy something a bit different.

[ge_rik]

Interesting. It looks as if they moved the signals between the two photos. In the one above, the 'inner' is beside the turnout to the carriage shed. I my later one the inner is by the leading turnout for the station.

OTTOMH, I don't think anything changed at Southwold, but I will dig around. I've found some of my virtual notes on one level of this machine, but I need to dig a bit deeper as I think there are more notes on the preserved desktop of the next further machine back in time.

I think you're right. Here's another later picture of the station with the inner still beside the carriage siding. I think there's some foreshortening of perspective in your shot - presumably taken with a long lens.



Rik

[Marquis DeCarabas]

I think you're right. Here's another later picture of the station with the inner still beside the carriage siding. I think there's some foreshortening of perspective in your shot - presumably taken with a long lens.

Ah, yes. That's Fanny Foster's picture. Note that the further signal has had the shunting arm added and a small bothy erected.

I've found some notes on the 'net that I wrote up nearly 2 years ago

MdeC did indeed suggest that.

As MdeC's 'social secretary' (as it were) I can say it was multi-section TS&T, not OES. There were sections with Annett's Keys for the control of a swingbridge groundframe and the mid-section groundframe for the locomotive shed.

There was a conventional groundframe at Blythburgh working the signals only - 5 levers (as there was a distant on one side of Blythburgh) with 2 Homes and Starters.

Elsewhere there were the 'Spinning Top' type flop-over handlevers, but there were forked drilled rods worked by the stretchers - the points had to be in the correct position or lie for the hole to align with a 'dart' [1] worked off the pushrod for the arm to go through the drilled rod. An 'off' signal would lock the rod with the 'dart' so the points could not be thrown with the signal off.

The fishtail arm caused an extra stretcher to be added to the first points at Southwold, presumably as the forked detectors only worked when the station throat points were normal and the fishtail read into the goods yard.

[1] think LNW tumbler conditional locking, but upside down.. I'll rummage around and get up some illustrations. I found the Southwold signalling regulations last night.

As regards the groundframe and signalbox at Blythburgh - this was another anachronism the groundframe was for signals only, but did include an additional Distant by Blythburgh Church.



Blythburgh GF - not sure of the design, but will work on it.



Blythburgh "SB", note the elevated signal in the distance.



Close up pf the Bothy in Fanny Foster's pic. Note the fishtail arm.

One other thing that is worth commenting about: the design of the Staffs is very close (if not identical) to the Glanrafon Annett's Key (later run round GF lock) on the NWNG - same contractor.

What else can I remember/dig up (still can't find Honky-Tonk's book):
There were eventually 3 sections and two loops; in 1879 the line was run as one OES section, Omnibus Telephone in 1899, following goods trains proposed in 1902. Passing Loop at Blythburgh made in 1908. TS&T Sections Halesworth - Blythburgh - Southwold. Harbour Branch opened. Great War saw Blythburgh/Southwold section split at Walberswick. Walberswick closed for block purposes during 1920 when harbour branch fell into disuse.

Omnibus Codes:
Halesworth 5
Wenhaston 4
Blythburgh 3
Walberswick 2
Southwold 1

[Soar Valley Light]

Gentlemen,

Thanks for your contributions to this topic. They are extremely interesting. They provide a perspective on early signalling which probably survived far longer on these narrow gauge lines than was the case on the bigger railways.

One is left to speculate how things may have developed if the Light Railways act hadn't come along, indeed, whether they would have developed at all in some cases!

Thanks for the Pothmadog diagram MdeC, that is fsacinating and very informative.

Regards,

Andrew

[Marquis DeCarabas]

G

Thanks for the Pothmadog diagram MdeC, that is fsacinating and very informative.

If you're interested, I do have some more. Including signalling schemes that were never implemented.

I also have drawings of a mixed gauge Portmadoc with 2' and 3' gauge track through the station - that's something I'd love to see modelled.

[Soar Valley Light]

One thing is for certain, I'm always interested in more, in fact I've never had enough!

Mixed gauge at Portmadoc? was that just a proposal or did it ever actually exist? This topic seems to stretch my knowledge daily!

Signalled mixed gauge layouts must have been a fairly rare thing in this country. (I'm sure the GWR had a monopoly on such things).

Your knowledge of these matters is a wonder in itself MdeC!

With grateful thanks,

Andrew

[IrishPeter]

IIRC the Tramway that ran northwest out of Porthmadog (Gorseddua Tramway c.1842-1871) was 3' gauge during its relative brief history. It served the same wharves as the Croesor Tramway which would have entailed 2' and 3' mixed gauge trackwork. The Gorseddau Tramway was eventually rebuilt as a 2' gauge line and extended to serve the Bangor Slate and Slab Co. Mine, which provided to be more of a bottomless pit than anything else.

One small point about the BOT and interlocking of points and signals - they did not care how you did it so long as it was reasonably tamper proof. The signals only frame whilst unusual, was not exactly rare in the early days. Locally controlled points would lock the mainline signals to protect shunting movements, which is a reasonably adequate precaution on a reasonably quiet line, and prevents an early common cause of collisions. In Australia this type of frame was elevated into an art form by introducing local interlocking of points via Annet's Keys. The Key was removed from the signal frame by reversing a lever which could not then be normalized until the key was returned to the frame. This would have the consequence of locking the parts of the frame that produced conflicting movements whilst eliminating the cost of extensive point rodding.

Peter in AZ

[Marquis DeCarabas]

IIRC the Tramway that ran northwest out of Porthmadog (GorseddauTramway c.1842-1871) was 3' gauge during its relative brief history.

It was 3' gauge until 1871 - I have some of the notices to treatabout the regauging. (as in original Gorseddau paperwork, fas -cin-ating)

It is perfectly possible that there was a mixed gauge signalled location at Port - there certainly seems to have been a local 3' gauge network around Pen Cei until the 1880s. what seems to have killed it off was the rebuilding of the Sluice Bridge (what is nowadays referred to as Britannia Bridge) there was a planned temporary 2' gauge bridge with isolated 3' gauge either side.

I have a copy of an 1845 drawing that is all 2' gauge, then about 1862/3 there is a mixed gauge track coming in from the North and going out across the Cob, the nearest track to the sea through Harbour station was mixed (..but..) the drawing has the station plan at ninety degrees to what was originally planned.

What is clear is that the original weighing machine house was going to be converted to the left luggage office for the passengers and later became the site for the bothy.

It is likely that at some point between the erecting of the semaphore and the introduction of Little Wonder that there was 3' gauge through Harbour, along the original breakwater.

We see but through a glass, darkly.

For proper narrow-gauge mixed gauge 'block' signalling we would need to move into the land where every mechanical signal was a different shape according to its intent...

[Soar Valley Light]

A thought struck me the other day when I was explaining some signalling basics during a Safe System of work training day (naturally!). When people talk about 'signalling' it strikes me that a significant number are referring to the sort mechanical signalling with which we have been familiar for (around) the last hundred years. By that I mean home and distant signals with blades connected to the spectacle plate and pivoted in a casting bolted to the side of the post and moving in front of the post. These signals being worked (most probably) by wire from a lever frame of the type that we still find in boxes and ground frames to this day.

This 'standardised' type of signalling appears (to me) to have developed into this form around the turn of the twentieth century, possibly a little earlier. This, by chance, seems to have been roughly co-incident with the Light Railways act which (as previously stated in this topic) relieved minor railways of the need to signal at all in many circumstances.

All this means that the more extensively signalled narrow gauge locations would be using signalling equipment of a much earlier generation. This is clearly illustrated in this topic by the pictures of the Southwold and by MdeC's excellent signalling diagrams of Port. The difference in type, standard, meaning and use of such signalling, not to mention it's means of operation, thus seem almost to be a different animal.

This is turning out to be a far wider ranging topic than I ever imagined would be the case. Having made some fairly sweeping and wide open comments here I shall await the volley of brickbats which I expect will be heading my way shortly!

Andrew

[IrishPeter]

The older parts of the Isle of Man Railway used slotted post semaphore signals controlled by 'ship's wheels', and weighted levers for the points.  No interlocking at all in the 1873/4 installations because on a relatively lightly trafficked line it was considered unnecessary at the time.  One oddity is that the signals are placed well ahead of the point being guarded so as to allow time to pull up between sighting the signal and the obstacle that required protection.

The MNR (1879) was a little more modern - semaphores, and compensated Stevens levers - but still no interlocking except at the running junction at St John's - and not centralized control of points and signals.  Move forwards another five years and St John's (Foxdale Jct.), the MNR new station of 1884, and Foxdale all had ground frames with the running points and signals centrally controlled being installed 1884-1885, but there were only homes and distants (if required) and no starters.

It is only with Douglas resignalling in 1892 that what we think of as modern mechanical signalling appears.  That said, there are still some archaic features such as stacking the arms for diverging routes, and the single line staff and ticket operations are in the hands of the stationmaster.

I think the Isle of Man Railway's signalling rather neatly tracks the development from the rather incidental signalling arrangements c.1870 to something close to 'modern' mechanical signalling.

Peter in AZ

[Marquis DeCarabas]

This 'standardised' type of signalling appears (to me) to have developed into this form around the turn of the twentieth century, possibly a little earlier. This, by chance, seems to have been roughly co-incident with the Light Railways act which (as previously stated in this topic) relieved minor railways of the need to signal at all in many circumstances.

I think you're about 30 years out, TBH. The Southwold is a little anomaly, as it was a 'light railway' before the light railways act that we all know about - there was some precursor legislation that allowed light railways of a form to be built. The only contractor that I can remember doing this is Arthur Pain who was the contractor for the Southwold. in fact it was <tippetty-tap> the Regulation of Railways Act of 1868 included provisions for railways to be constructed as light railways. Such railways could be constructed more lightly than normally required but incurred a maximum axle loading of 8 tons and a maximum speed limit of 25 mph. Arthur Pain, the engineer of the Southwold, was perhaps the main proponent of such light railways and very few were constructed, not least because an expensive Act of Parliament was still required.

All this means that the more extensively signalled narrow gauge locations would be using signalling equipment of a much earlier generation. This is clearly illustrated in this topic by the pictures of the Southwold and by MdeC's excellent signalling diagrams of Port. The difference in type, standard, meaning and use of such signalling, not to mention it's means of operation, thus seem almost to be a different animal.

Yes; partly. Thus far you've had in the discussion the Southwold and the Festiniog. Now, the Southwold was constructed in 1879 as a 'lighter' railway, the Festiniog was constructed in 1832 as a horse tramway and converted to a passenger line in 1863/4. It is actually sheer coincidence that both railways have double arm semaphores.

If we begin with the FR, it was signalled to the contemporary standards of the early 1860s, and by the time the signalling fell into desuetude in 1926 I suggest that the surviving double arm semaphores (Port, Minffordd, TyB and TyG) were the last 'block' semaphores left in the UK that were not at a stopping point. By the time TyB opened and Minffordd was constructed (1871-4) the signalling system was already old hat - separate signals were provided at stopping points. The shape of Distants were very much a moveable feast - the FR stuck with the Disc signals until the end of signalling, although [and this is axiomatic to any understanding of FR signalling, in the majority of cases after the introduction of the 1876 rulebook (which was still largely in force until the (a guess) early 1930s)] the Discs were *not* Distants - they were 'Auxiliaries' (an old term for outer homes) or Stop signals. Trust me on this, it's something that really confused Boyd. i could go into at length, but the arcana of Festiniog signalling is an acquired taste.

However, if you'll indulge me a little longer on the FR, you may find this interesting. Take a look at this proposal for Portmadoc:




Now, this isn't the only proposal for resignalling Portmadoc at the time of the 1879/1880 rebuilding, but if you look at the style of the signalling, it is much the same as you would find on any pregrouping railway in the UK mainland up until about the time of the Great War.

Now, you may be wondering why the 'old' style signalling survived at Portmadoc until 1921 and what caused the FR to change its signalling style? In truth I'm not sure what happened at Port, as this tender was accepted, but never enacted. The second part is a bit more complex, and FWIW, the real reason is only just becoming clear - the fashions were not directly related to the Regulation of Railways Act of 1889 after Armagh, as some have thought. It was a far more interesting reason.

Many of you, I'm sure will be well aware of the vast plans for the North Wales Narrow Gauge Railways, that came to naught and were only embodied in the Moel Tryfan undertaking. There was also another pair of plans (ignoring the Merionethshire Railway for the present, as that didn't really take on a tangible form at all) - there were the Bala and Festiniog Railway and the Bettws-y-Coed and Festiniog Railway. Both were predominantly promoted by the rival standard gauge companies - the B&F by the GWR and the earlier ByC&FR by the LNWR. I have plans for both of these sat by my machine and if both had been built, the signalling of the Duffws branch would have been fantastic. The B&F was largely on the course of the F&B, which as we all know was regauged in 1883 *but* there was a plan for the B&F to continue up as far as Rhiwbryfdir! Now, don't forget that the LNW were planning to come south with a 2' line, broadly on the course of the later standard gauge: this was planned as early as 1873/1874 - the Bala and Festiniog was a direct competitor - so imagine if you can the FR lines in Blaenau, with a 2' gauge line coming in from the North and and another coming in from the East.

So? What's this got to do with signalling. Well, although the FR had gone to Parliament in 1869 to double track, very little had actually taken place. I'm currently unpicking the signalling history from Old Dinas Junction eastwards towards Duffws, and trying to actually pin down a date of when the second track was laid - be it throughout or piecemeal is quite difficult. The only certainty is that the was a bridge built (Church Street) for the Portmadoc and Beaver Pool turnpike in 1875 and in 1870 Duffws station was rebuilt into the form that is now preserved as public loos.

Cutting a very complicated story short: what is clear from the plans of the B&F is that they wanted their own right of way around the FR towards Rhiwbryfdir, crossing over the FR somewhere near the later LNW exchange station and the level crossing at Glanypwll, according to the 1873 plans. The ByC&F coming in from the North adopted a different strategy: in 1871/2 it was originally planned to terminate below Rhiwbryfdir Fields, but in 1874 the drive changed and there was going to be a big terminus on the site of the later North Western Hotel with a branch and junction towards the Festiniog terminus at Duffws.

This is the game-changer with FR signalling. Unlike the Festiniog and Blaenau this would have taken both goods and highly likely to have had passenger traffic from Duffws to Bettws. The FR Board discussed running powers at some length. The F&B junction (christened by Boyd to be 'Dolgarreg-ddu' Junction) was only ever for goods traffic, and as such the existing FR signalling could cope, with the Disc signal outside Duffws moving down the line to protect the junction (I have the plans sat next to this machine) but the existing FR signalling could not cope with an inspection from the Ministry if passenger traffic were to use the new junction both ways. A lot had changed with signalling even in the short period from 1868 when the F&B arrived to 1874 when the LNW were pushing southwards.

Although I have not yet found (and nor do I expect to find) a signalling diagram for the upper junction (ByC&FR/FR junction) it is this discussion of running powers that will have put proper signalling in the minds of the Directors. The earliest full signalling plan I can find for the area is dated December 1877 and that is semaphores everywhere - by 1879 the 'middle' bit of the Duffws branch would have been not only doubled (the Board discussed this in the summer of 1874) but the signalbox that later became Blaenau No 2 would have been in situ. Although in the end it came to naught, the FR's hand would have been forced by the desire of the ByC&FR to run into Duffws - This is I suspect part of the delay between the rebuilding of Duffws station into distinctly separate parts called the 'Goods Station' and 'Passenger Station' in 1870 and the eventual doubling during 1875 - the FR board were waiting to see what (in effect) the LNW and GW were actually going to do. All the traffic being handled out of Duffws on a single line would have caused an incredible bottleneck. I feel that this is the explanation for why there was 'conventional' signalling east of and including Old Dinas Junction.

The Portmadoc signalling plan is very much in the vogue of the time and I offer it as a counterpoint to the 1921 diagram, and it would be a pleasant exercise to work out what would have happened at Blaenau, but we must be chary of creating false history.

This is turning out to be a far wider ranging topic than I ever imagined would be the case. Having made some fairly sweeping and wide open comments here I shall await the volley of brickbats which I expect will be heading my way shortly!

Moving away from the FR, it would be instructive to look at 'proper' light railways, and their signalling, constructed under the 1896 Act. You might be in for a pleasant surprise, a couple of examples.

Both of these are ostensibly the same, though with the addition of a siding at one. It would have been more germane to use Capel Bangor as one of the examples, as like Castle Caereinion there were summer and winter frames. However, Capel Bangor had economic locks and that can confuse the unwary, so I've decided to use Aberffrwd instead. These two installations are nearly contemporary, but there are important stylistic differences, probably due to the fact that Castle Caereinion was manned irregularly. However, they were both later additions to the original railway: Aberffrwdd in 1904 and Castle Caereinion in 1907.







Aberffrwdd was going to be regularly used to cross a pair of passenger trains, so had starting signals, but no signalbox. Castle Caereinion was to be used for a couple of months at a time and otherwise the groundframes would be used unless there was a crossing between a passenger and a timber train. As a result, Castle had Distants, but no Starters and did have a signalbox. Consistency, eh?