An introduction to mechanical railway signalling
in the Derby area
Even the most casual of observers cannot have failed to noticed that the railway network around Derby is but a shadow of its former self. Where once were acres of marshalling yards are now shops. Where busy branch lines once veered off there is impenetrable jungle as nature reasserts her rights. The railway has changed dramatically over the years; gone are the steam engines, gone too are most of the diesels which replaced them, usurped by a new generation of motive power.
One change which won't be so obvious to said casual observer is the manner in which the trains are controlled on the lines that are left. Once a familiar part of the railway landscape, the signal box is now a rarity indeed. A few remain, their short-term future arising from the financial woes of Railtrack and Network Rail, their most recent custodians. Perhaps not yet in danger of extinction but surely on borrowed time.
Where once there were over two hundred there is now one — a “Power Signal Box” (or PSB), itself just short of 50 years old. Derby Power Box controls trains from Wichnor to Wingfield, Draycott to Drakelow and all in between. Though, of course, there is a lot less in between than there once was.
This article seeks to shed some light on the development of the railway signalling around Derby, both from a technical and a social perspective.
Derby's railway history begins before Victoria took the throne but in those days the control of the trains was left to a lot of luck and just a little judgement as all that prevented one from running into another was the interval of time between them. A train was prevented from leaving a station by a policeman and a flag until sufficient time had elapsed to allow the previous train to reach its destination. When things ran well that was all that was needed but as the trains became faster, when one ran out of course or - worse - stopped unexpectedly, there was little to protect them.
All this changed with the introduction of the electric telegraph, at this time little more than a needle which was deflected one way or another by the transmission of electrical pulses. This allowed a safer system to develop where trains could not set off toward a station before positive confirmation had been received that the previous train had passed clear. Around the same time the flag gave way to fixed signals which partially imitated the semaphore code of old. In addition to all this, it became the practice to allow points to be switched from one position or another remotely by means of a series of wires (later rods).
Thus around the 1860's the control of these three elements began to be centralised in one place. Even though the world of the railwayman was harsh in those pioneering days, the men who were to control these apparatus were afforded shelter and the signal box had arrived.
Despite being fiercely traditional in many ways, the railway has always been an innovative industry. In the same way that locomotives became faster and more powerful and rolling stock became more comfortable, so too over time the signalling has been refined and perfected.
The simple telegraph communication evolved into a sophisticated set of rules known as the Block Telegraph Regulations. This involved an elaborate ritual performed by the signalmen along the line in co-operation with one another. The first would, using a bell code, ask his mate in the next box “Is Line Clear For….?”. Four beats of the bell meant “Is Line Clear For Express Passenger Train?”, Three beats followed by two beats signifying a goods train. If the line was indeed clear up to a set point behind his signals (far enough should the next train not slow down enough and pass the first signal), he would answer “Yes” by repeating the bell signal. As a visual reminder the needle of the telegraph instrument would be moved by the accepting signalman so that it was held in a position marked "Line Clear" on the sending man's instrument.
The signals could now be cleared and as the train entered to section of line between the two boxes the signalman sending the train on would send two beats on his bell to let his mate know. At the receiving box the signalman would change the position of the needle to “Train On Line” and would be beginning the process all over again with the next box along the line.
When the train had passed through the section the signalman would check that it had arrived complete with the tail lamp that, to this day, must be carried on the rear of all trains. He would send the "Train Out of Section" signal (two beats followed by one beat) to the box that had sent the train. The instrument was then returned to its normal position which was "Line Blocked", for so it was assumed until the procedure was repeated for the next train.
The Victorian railway was run by dozens of companies, which, although each had its own geographic stronghold, were all competing with one another and whose lines often cris-crossed as they vied for traffic from the same localities. Despite the commercial competition, pressure from a Governmental body known as the Board of Trade resulted in all the companies using broadly similar operating methods for their signalling.
Derby was the heart of a network of lines operated by the Midland Railway Company from London St. Pancras to Carlisle and Bristol to Leeds. Although other companies managed to obtain a token presence (the North Staffordshire Railway, the London and North Western Railway and, later the Great Northern Railway), Derby was a Midland town.
As Derby was their headquarters, the Midland sited their signal works in the town - as well as the much better known Locomotive Works and Carriage & Wagon Works. The signal works occupied the site now home to the Derby Evening Telegraph and it was here that all the Midland's signal boxes, lever frames and block instruments were crafted.
The Midland had a reputation for doing things differently to the other companies. On the passenger front, for example, they introduced a two class system by abolishing second class long before the rest of the railway followed suit. So it was with their signalling. Within the standards laid down by the Board of Trade, the Midland refined the Block system into an even safer regime by locking the instrument until the train had passed over a treadle at the receiving end. To accommodate this, the indication on the Block instrument, instead of being turned one way then the other, went round in a continuous three position circle, giving the system its name of Rotary Interlocking Block.
On a less technical level, the signal boxes and even the signals themselves were subtly different on the Midland. The structures they provided for their signalmen were almost universally of timber construction and were prefabricated at Derby. The sections (or “flakes” as they were known) were transported to the site of a new signal box and bolted together. A local builder would then be contracted to slate the roof and the signalling equipment would be installed in the box.
Timber is traditionally a short term, even temporary, method of building. The Midland could employ this method of constructing signal boxes as they were not intended to last very long. In the boom years of pre-First World War Britain, the railways were continually growing. As more capacity was required, it was built. That meant that the signalling was in need of regular revision to cope with revised layouts. When this happened the Midland would simply build a new, bigger, signal box.
Not that the company went in for really big boxes. Only rarely were boxes built longer than 30 feet or more than 50 levers. As in other facets of their operations, the Midland favoured little and often. A relatively small area - Derby station being one such area - would have numerous signal boxes, each controlling a small area or limited number of running lines. In the case of Derby station, at its height there were six signal boxes within its immediate confines; London Road Junction, Derby Station ‘A’, Derby Station ‘B’, Engine Sidings No.1, Engine Sidings No.2 and Derby Station North Junction.
The design of the Midland signal box changed very little over the years being remarkably standardised, due to their pre-fabricated nature. Indeed, over the 70, or so, years during which they were being built there were only three obvious design changes and even those weren't radical. There were some non-standard oddities though. The aforementioned Derby Station ‘A’ was a quite ornate affair built in such a way as to blend in with the station building that surrounded it. A 1910 replacement of two earlier boxes at Matlock Bridge (as the station was then titled) was carried on a gantry which straddled one of its sidings.
Burton on Trent was famous for its network of brewery railways which riddled the town. At one time there were over 30 level crossings in the town, many of which were controlled by a signal box, some privately owned by the brewers, others by the Midland. Continuing the theme of odd Midland signal boxes, High Street box was literally wedged into a small space near to what is known as Bargates today. The shape of its site resulted in the box being a mere 3 feet wide at one end, tapering out to a more conventional 5 feet at the end that overlooked the roadway. Remember that the unfortunate signalman needed to be able to pull the levers in that width to clear his signals.
Thus far little heed has been paid to the other railway companies who operated into the Derby area. The North Staffordshire Railway was centred on the Potteries but built a line through Uttoxeter that joined with the Midland's Birmingham to Derby route near Willington. The junction was controlled by the appropriately titled North Stafford Junction signal box. The same name was, confusingly, bestowed at the junction with that company's Tutbury branch at Burton, less than five miles down the line.
The London & North Western network traced its way from London Euston, along the west coast toward Scotland. It spread its tentacles toward the lucrative ale market of Burton on Trent and built a few small lines of its own in that area. Only two LNWR signal boxes were built in the area, Burton Goods Yard and Allsopp's Sidings now buried under a housing estate at Shobnall. The LNWR did lend its name to a Midland signal box on the outskirts of Derby, controlling the lines that veered off to that company's St Andrews Goods Yard.
For their part, the Great Northern Railway were the late comers in 1878, tempted from their east coast stronghold by the Derbyshire coal field and, again, Burton Ale. They built a line from Nottingham, through West Hallam and Breadsall to Derby, where they built Friargate station. The line continued via Mickleover and Etwall before joining the North Staffordshire's line at Egginton Junction. A further short spur from Egginton Junction formed a triangle with the North Stafford's Burton line bringing into being the remote, but very picturesque, Dove Junction signal box.
The prosperity and expansion of the railway suffered a complete about-face with the Great War. With the Armistice came a decline which continued virtually unchecked to, and perhaps beyond, today. Rationalisation became the order of the day. Some passenger services from Derby to Ripley, Heanor, Wirksworth and Melbourne were suspended as a war time economy measure, some never to restart.
As the use of electricity in railway signalling became more commonplace so did its influence. Points could be moved from much further away and the presence of a train could be detected by the short-circuiting of a small current running along the rails. Early implementations of power signalling allowed many intermediate signal boxes to be abolished. Track circuiting meant that where a man was once required simply to see that a train had passed, that function could be done remotely by what was known as an "Intermediate Block Section". So as the depression of the inter-war years began to bite, the three signalmen each once employed at Hargate (near Willington), Osmaston Road, North Stafford Junction, Chellaston East Junction, Bull Bridge and Johnson's Sidings (near Whatstandwell) all joined the ranks of the unemployed.
In 1923 things had become so bad that the Government stepped in and forced the railway companies to amalgamate. Thus the Midland merged with its former competitors to become the London Midland & Scottish. The Great Northern was firmly part of the London and North Eastern Railway upon what became known as ‘grouping'. Thus Derby was served by both companies.
Fierce company rivalries flourished under the new regime, both on the 'shop floor' and more especially, in the board room. At first it was pretty much "business as usual". New boxes built under the auspices of the LMS at Branston Junction and, for the first time on non-Midland territory, Etwall Goods, were still of Midland design. Derby signal works lingered on but as its work was duplicitous, it was closed in 1928 and its functions moved to Crewe.
The LMS began building signal boxes which were an amalgam of Midland and, mainly, LNWR styles. Most significantly these boxes were, in the main, built of brick to floor level with only the operating floor area being timber. Ironically, the first of these boxes were put up in the Derby area, at Broadholme and Ambergate South Junction, in connection with the widening of the line into four tracks between those places.
Renewals of signalboxes slowed down dramatically in the LMS era. Of the few other LMS boxes which appeared in the Derby area, the outbreak of the Second World War and the consequent leap in railway traffic was the catalyst. A new box was built to control sidings put in at the Royal Ordnance Depot built at Sunny Hill. Coton Park colliery near Gresley was reopened and its connection required a new box.
The boom was short-lived (given its cause, mercifully so). Once again war had ravaged the railway and the post-war Labour government stepped in with Nationalisation. British Railways (London Midland Region) was at first slow to make changes. Sure enough a new design of signalbox appeared and was used to replace some Midland structures which were now long past their intended life-span. Derby North Junction, just across the line from the former signal works, was one such renewal. So too was Lock Lane Crossing near Long Eaton on the Stenson Junction to Sheet Stores Junction line that by-passed Derby to the south.
An industry that was expanding at this time was electricity generation. The British Energy Authority were building a network of large coal fired power stations along the Trent Valley. Derby's railway network was to bring in the fuel from the multitude of coalfields in South Derbyshire, Ripley and along the Notts/Derby border. This necessitated vast new sidings at Castle Donington, Willington and Drakelow. The existing Midland Railway box at Castle Donington was adequate there but a replacement structure was needed at Stenson Junction (at the rear of Willington Power Station). At Drakelow a new double junction was required and a signalbox was built to operate it.
Although they were both built in spring of 1954, the new Stenson Junction box was built to the, then, standard LMR signal box design, but politics were at work within BR in the case of Drakelow box. Traditionally signal boxes had been designed by the Signal Engineer's Department as it was they who required them. This did not sit comfortably with the architect's department who saw designing any building as their job. So with Drakelow the architects asserted themselves and set about "designing" rather than simply using an ‘off-the-peg' signal box. The result was an odd looking structure to the eye of most observers.
By the time Willington power station opened the signalman at Stenson Junction, who was already a busy man, had 12 different directions from which trains could arrive or depart. As well as controlling trains on the main line between Birmingham and Derby by working with Willington and Sunny Hill boxes respectively, there were junctions with the North Staffs line worked toward Willington Crossing and the line to Long Eaton where Chellaston Junction was the neighbouring box. An added complication was that there were two lines in each direction toward Derby, so the signalman had to decide when to turn slower trains into the goods line or when to let them out in the other direction.
To help him with this task, the lone signalman at Stenson Junction had a ‘booking boy' who relieved him of the necessary burden of keeping the Train Register in which the time each and every bell signal was sent or received. In addition the ‘lad' would help out by making and receiving telephone calls from surrounding signal boxes so that the signalman would know exactly when to expect the next train in any direction.
London Road Junction signal box was, arguably, even busier. This is reflected by the fact that there were two signalmen and a “booking boy” here. The 83 lever box controlled the south end of Derby Station. As well as the six platforms there were two goods lines running round the back of the station. Trains along platforms 1 to 4 were dealt with in conjunction with Derby ‘A’ box, sited halfway along platforms 3 / 4. Platform 5 was (and still is) a dead-end “bay” but trains along Platform 6 were belled-on from Derby Station North Junction at the other end of the station. The neighbouring box on the goods lines, however, was Engine Sidings No.1.
In the other direction, the lines converged before splitting south toward Nottingham, where the next box was Way & Works Sidings or west toward Birmingham, in which direction both passenger and goods lines were provided. Until 1932 the next box on the western line was Osmaston Road, although advances in technology allowed that box to be replaced with an "Intermediate Block Section". This meant that London Road Junction now worked with LNW Junction, 1,690 yards away. The layout at London Road Junction was such that two trains could not enter the station from Nottingham and Birmingham at the same time. They could, however, depart in those directions simultaneously, if required. This meant that with all the shunting to and from the station and the nearby Carriage and Wagon works, the signalmen at London Road Junction had to be extremely skilful and efficient to work their trains in and out without delay.
Not every signal box was host to such frenetic activity. There would often be periods when some intermediate signal boxes were not required. This would usually be either overnight or during weekend periods either because there was no traffic due to call at the intermediate sidings or because the volume of traffic didn't require such close spacing of block posts. Most boxes were therefore fitted with a "Block Switch" which allowed the two adjoining Block Sections to be linked and the intermediate box to close overnight or until Monday morning.
It is interesting to note that the few boxes that weren't provided with Block Switches were the small wayside boxes such as Matlock Bath. This was because, being a less busy box, the signalman's rate of pay was less, thus it was cheaper to keep that box open continuously than its neighbour on a higher rate!
Whilst the main lines were kept open for traffic all the time (even Christmas Day until comparatively recently), the branch lines would close at nights and, often, on Sundays as well. There would be much consternation amongst the signalmen if the last train on a Saturday evening was delayed and kept them at work late!
It will be noted that the term “signalman” has been used liberally. Like so much of the labour market of the time, the railway was the virtually exclusive province of men. Women had been drafted in to the signal boxes during the war, notably along the Great Northern line, and several remained afterwards. The post of crossing keeper was also one which was often filled by women, perhaps as it was usually a residential job and may have been considered compatible with being a “part-time housewife”!?
Inside the signal box, there would be a long line of steel levers, usually but not always, at the front of the box overlooking the railway outside. The levers were brightly coloured according to the function they performed and each was numbered, always from left to right. Above the lever frame would be a shelf upon which the block instruments, telephones and various indicators would be fixed. Above that a diagram showing the layout of the lines the signal box controlled with the points and signals numbered to match the frame.
Boxes that controlled level crossings, might have a huge wheel which the signalman would wind furiously to move the vast weight of his four wooden gates through 90º. Such contraptions were fitted at Breadsall Crossing where the A38 crossed the line before being bridged in 1969, as it did at Derby Road Crossing at Willington. At Burton Station South there was a particularly wide level crossing where Moor Street intersected the line. A subway was provided here and all but the biggest of vehicles were expected to use it, hence the gates were usually kept shut across the road. Rumour has it that if a car driver came up to the gates and expected them to be opened, such was the effort required to move the gates, the signalman might pull of his goods line signals as though a train was due and hope that the motorist got bored and went under the under-pass!
Elsewhere in the box there would be a desk, at a convenient height to stand at rather than sit at. The desk was home to the Train Register and would be surrounded by sheaves of paper; the timetable, notices of special trains, notices of work being carried out on the line and other documents of varying degrees of permanence relating to the working of that box. Every signalman would know the contents of these notices by heart, at least the parts that were applicable to him.
In Midland days the signal boxes were traditionally kept very dark inside with only enough light to see the Train Register. This was because the signalman was expected to record the numbers of passing trains and read a code that was displayed on goods trains relating to their destination. Many boxes remained lit by gas or, more usually, paraffin until the end.
To cater for the signalman's welfare a fire (coal, usually fed by fuel dropped off by passing locomotives) and a stove were provided. Invariably there would be a comfy chair of some dubious vintage having been retired from some signalman's home, perhaps with an off-cut of carpet. More basic needs were catered for by an outside privvy, usually close to the bottom of the box steps, so that the block bells were still audible.
The work of the signalman could certainly be very physical. Most boxes would have a "distant" signal sited nearly a mile away from their box in each direction. To “pull off” that signal involved hauling on a lever and effectively dragging a mile of wire, which may cross and re-cross the line several times and go round bends, so that the arm of the signal would drop. (Prior to the 1920s semaphore signal arms were "lower quadrant", that is they dropped, whereas the more modern type of arm is raised to about 45º to signify clear. The lower quadrant arms were weighted so that if the controlling wire snapped, they would automatically return to the horizontal “danger” position).
Even the points, which were always comparatively close to the box if mechanically worked, were an effort. In their case the lever either pushed or pulled (and sometimes both!) a solid rod to move the switches. There was doubtless a knack to it and many a signalman has had a chuckle at the expense of an apparently fit and strong visitor struggling with a lever only to be humbled by the apparent ease at which the professional accomplishes the task.
As the years progressed, more and more of the points and signals became motor worked thus sparing the signalman's back a little. In order that the signalman didn't give a great heave on a lever that was motor worked with the result that he may topple back into the fire, the handle was shortened considerably so that one a single hand would fit.
In between the hectic activity associated with the passage of the train, there would often be quite long periods when little was happening. The time would be passed with keeping the box sparklingly cleaning or, perhaps, the preparation of a meal. Much more likely, however, time would be passed by chatting on the "omnibus telephone circuit".
Ostensibly provided by the railway so that signalmen from boxes along a particular line (or circuit) could keep one-another informed of the progress of trains, the " 'bus line" was more often a hotbed of gossip, intrigue, football, gardening, or virtually any subject under the sun. It was an odd situation that a signalman could quite possibly know everything there was to know about his mate in the next box, but because they would always work the same shift, they may not actually meet one another from one year to the next!
At a junction signal box the signalman would know which way to send a train thanks to a system of bell codes, particular to that box. This is best illustrated by example. At Spondon Junction a "Down" train (that is, one approaching Derby, "Up" usually being toward London) could either be routed straight ahead through Chaddesden or left toward Way & Works box and the south end of Derby Station. As a train passed Sawley signal box five miles away the driver would give a series of whistles dependant on his route at Spondon. The Sawley signalman would translate those whistles to bell codes and add them to the two beats he would send to Draycott box as the train entered the section. That would be the Draycott man's cue to ask "Is Line Clear For…?" to Borrowash box and in so doing he would again add on the routing code. Borrowash would do the same to Spondon Station who would pass it straight on to Spondon Junction 764 yards away, so that the man there had time to set the route accordingly and ensure his line was indeed clear to the relevant "clearing point" before accepting the train.
In some places, notably Ambergate where there were multiple directions a train could be sent, the routing bell codes were replaced by ‘ticks' on the needle a telegraph instrument, reminiscent of the very early days.
The late 1950's was to be the beginning of the end for mechanical signalling. At that time, in addition to the traffic generated by such as the coal industry, almost every station had at least a couple of sidings at which it could send and receive the sundry goods that the railway, as a "common carrier", was required to handle. By the 1960's, however, the railways were beaten by road transport.
As the traffic declined the once comprehensive infrastructure was being dismantled with increasing rapidity. So too the need for so many signal boxes to control the network dwindled. Whole lines closed, such as the Crich Junction to Swanwick branch, taking with it boxes at Buckland Hollow and Butterley. Other lines were radically cut back; the Ripley branch was severed at Marehay Crossing and later at Denby.
Main lines closed too, the Great Northern line from Nottingham Victoria to Derby Friargate and beyond suffered most from the politics of the day and was deliberately run-down before being killed in May 1968. Most grievous and, arguably, short-sighted of all was the closure of the Midland Main Line to Manchester. A truncated single line branch to Matlock is all that remains today.
Ambergate was, until then, a railway community. As well as the famous triangular station, the complex of lines required signal boxes at Ambergate South Junction, Ambergate Station Junction, Ambergate West Junction and Ambergate North Junction. The latter box had a fairly extensive collection of sidings lying between itself and Crich Junction at nearby Bull Bridge. All of which was cleared away.
As the railway network contracted it became possible to rationalise and simplify layouts. No longer was there a need to squeeze so many trains through. With the simplified layout came centralised control and Derby Power Box.
Derby PSB opened in three stages, taking control of the lines to the west of Willington first on 16th June 1969. A fortnight later the colour light signals were switched on along the rest of the western lines from London Road Junction. The final stage was completed by Monday 14th July and mechanical main line signalling in the Derby area was consigned to history, as were the jobs of many of the men who worked in the 40 or so boxes closed by the scheme.
There were survivors; although only a vestige of the Burton Brewery system remained, it was too complicated to be run from Derby so former main line boxes at Horninglow Bridge and Wetmore Sidings were retained as shunt frames as was Clay Mills Junction, to control a level crossing. Spondon Station box survived in a similar capacity. Chaddesden sidings were still quite busy and Chaddesden South Junction and Derby South Junction were retained to control traffic there. Indicative of the goods traffic still around Derby, St. Mary's Goods Yard was also still busy enough to retain its signal box as a shunting frame. Finally, the need to change locomotives at Derby Station resulted in Engine Sidings No.2 being retained to allow access to "Derby Four Shed", as the diesel depot is still known.
All this was a temporary reprieve as slowly but surely the traffic dried up and the yards were closed or at least significantly reduced. The economic slump of the mid- 1980's was the final nail and one-by-one the survivors succumbed. Locomotive haulage was being phased out in favour of fixed formation "High Speed Trains" so Engine Sidings No.2 closed in 1987. Closed circuit television cameras eventually made Clay Mills and, last one of all, Spondon crossing boxes redundant and they too were demolished.
Despite plans to the contrary, however, Derby Power Box was never expanded. Consequently mechanical signalling is alive and reasonably well on the North Staffordshire line. Although rationalisations have taken place, signal boxes remain at Egginton Junction, Tutbury Crossing (believed to be the oldest operational signal box in the country, now) Scropton, Sudbury and Uttoxeter. Lock Lane Crossing was a survivor into the 21st Century as a gate box under the control of Trent power box. The arrival of the East Midlands Signalling Control Centre at Derby, has seen much of Trent PSB's 1969 infrastructure swept away — including the power box itself on 28th July 2013. Derby PSB, ironically given its proximity to the new super power box, will be the last in the area to be subsumed by it in the summer of 2018 — just a year short of its own half-century.
In the event that you have a desire to see a Midland Railway signal box there are survivors quite close by. Several are preserved locally to Derby; at the Midland Railway - Butterley, the Ecclesbourne Valley Railway at Wirksworth and Peak Rail, Darley Dale. Network Rail still operate several Midland Boxes, Moira West Junction at Overseal being the closest to Derby.
In addition, on the Lincoln Line there are four Midland and two LMS era signal boxes still controlling trains on the Absolute Block system. Most notable is Lowdham signal box which is now well over 100 years old - not bad for a building that was built with a life expectancy of about thirty years! Regrettably, but understandably, all but Swinderby signal box were abolished by the "East Notts Resignalling Scheme" in Autumn 2016.
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Dave Harris, Willington, Derby, UK.
Page last updated: Saturday, 16 June 2018