Adjusting the clocks

[Rescars]

Changing to Summer Time has reminded me (again) which of my clocks do and don't change automatically, even in our digital age. Presumably a similar situation arises across the network even now, but it must have been even more complicated back in the fully analague/mechanical era. Can anyone please explain how, back in the day, the railways arranged for all their clocks to show accurate time consistently and to be adjusted promptly for seasonal time changes?

 

[DelW]

Changing to Summer Time has reminded me (again) which of my clocks do and don't change automatically, even in our digital age. Presumably a similar situation arises across the network even now, but it must have been even more complicated back in the fully analague/mechanical era. Can anyone please explain how, back in the day, the railways arranged for all their clocks to show accurate time consistently and to be adjusted promptly for seasonal time changes?

It's an interesting question - and might have been a bigger problem in the autumn, when clocks need to be set back an hour. I think that mechanical clocks don't like being moved backwards, so might have had to be set forward 11 hours, or stopped for an hour. Unless that only applies to striking or chiming clocks?

 

[Mcr Warrior]

Can anyone please explain how, back in the day, the railways arranged for all their clocks to show accurate time consistently and to be adjusted promptly for seasonal time changes?

Probably a lot more station staff around to do the adjustments?!

 

[Andy873]

A great question, I don't know about the railway situation, but all mechanical clocks don't like being put backwards which can cause damage.

 

[The exile]

Seem to remember that a time check would be done for signal boxes daily over the phone system so manual adjustments would have been a daily occurrence. The only difference here being the scale. I don’t know how it worked with accuracy down to the second as no analogue clicks I’ve met allow for the adjustment of the second hand except by temporarily stopping the click, which is then itself a bit hit and miss on the restart time. Maybe “master and slave” systems did allow for that.

== Doublepost prevention - post automatically merged: 29 Mar 2026 ==

A great question, I don't know about the railway situation, but all mechanical clocks don't like being put backwards which can cause damage.

But then moving the hands forward 11 hours instead of back 1 isn’t as much of an extra ordeal as it is with digital clocks which will only adjust forwards.

 

[Magdalia]

The railway had lots of mechanical clocks and surviving examples are now quite valuable:

Railway Clocks auctioned by GW Railwayana Auctions

Previous & Next auctions of Railway Clocks. Sell, buy or view Railway clocks Maximum price: £3,700, average price: £950, 539 items listed - GW Railwayana Auctions

www.gwra.co.uk

Railway Time was one of the most important aspects of running a railway safely and punctually. Just about every railway company had clocks produced for them and every signalbox, station and office would have a company railway clock adorning the wall. Hugely collectable today, not only companies such as LB&SCR, SER, SECR, GWR and constituent companies, but clocks from all over the system generate great interest. From small fusee wall clocks, large weight driven regulators or a fine bracket clock. There are fine examples of all of these that we have sold and have a resident Horologist who is one of the leading experts in this field.

I do quite a lot of research in signal box train registers. These include frequent references to the signal box clock being checked and adjusted, if necessary, though I don't know how the checking was done. There doesn't seem to be a pattern of when the clock was checked, though 6.30am and 10am are probably the most common times.

The signalman on duty would be responsible for adjusting the signal box clock at start and end of British Summer Time. That would be going forward from 2am to 3am in the spring and back from 3am to 2am in the autumn, and would be done as near as possible to those times. This adjustment would also be recorded in the train register.

I expect that, at stations, the station master on duty would have the same responsibility, and that would be how it worked in goods depots and locosheds too.

 

[DelW]

This morning's "Broadcasting House" on Radio 4 included an audio recording of the work done overnight last night to reset Big Ben*. It was broadcast at about 09:32 for anyone who wants to find it on Sounds.

*(I know that's the bell not the clock, but it's what almost everyone calls it)

 

[Gloster]

At signalboxes either the Saturday night man or the first person to open the box after the change would alter the clock and put an entry in the train register. As by my era there were no longer manned telephone exchanges during the night that could give out the time as they had done with the daily time-checks, we just had to use our common sense; of course we would never think of checking it against the radio as radios were banned in boxes, weren’t they.

In the early 1980s there would be a couple of S&T men who would spent Saturday night at Bristol Temple Meads altering all the station‘s clocks; two men were needed because of the amount of ladder work. I think that they planned the work with reference to which platforms, etc. were in use at different times.

 

[Ashley Hill]

Can anyone please explain how, back in the day, the railways arranged for all their clocks to show accurate time consistentl

Guards were expected to keep their pocket watches accurate and set them to the time on the clock at their depot. To find the time stations would simply ask the guard of the next train.

 

[Rescars]

Many thanks for all the responses so far.

Guards were expected to keep their pocket watches accurate and set them to the time on the clock at their depot. To find the time stations would simply ask the guard of the next train.

This raises a question in my mind. If the station staff wanted to check their and adjust their clocks, all well and good. But what if the station staff didn’t want to make adjustments yet the station's clocks and the guard's watch didn't agree? For instance, the station clock showed it was time for the train to leave, but the guard's watch says it was early. Whose timepiece took precedence?

 

[Gloster]

Many thanks for all the responses so far.

This raises a question in my mind. If the station staff wanted to check their and adjust their clocks, all well and good. But what if the station staff didn’t want to make adjustments yet the station's clocks and the guard's watch didn't agree? For instance, the station clock showed it was time for the train to leave, but the guard's watch says it was early. Whose timepiece took precedence?

The guard was in charge of the train, so he gave the Right Away when his watch said it was time, not when someone else or their clock said it was time. This was still the situation in the 1980s.

 

[Bald Rick]

But then moving the hands forward 11 hours instead of back 1 isn’t as much of an extra ordeal as it is with digital clocks which will only adjust forwards.

All my digital clocks adjust backwards!

 

[Fleetwood Boy]

Related question. How was potential confusion avoided when the hour went back in autumn? For example signal box registers would show a repeat hour and potential confusion about which 0100 someone was referring to (BST or GMT). Obviously less potential confusion when an hour is simply missed in the Spring.

Did it ever cause problems or confusion?

 

[RailwayRookie]

Related question. How was potential confusion avoided when the hour went back in autumn? For example signal box registers would show a repeat hour and potential confusion about which 0100 someone was referring to (BST or GMT). Obviously less potential confusion when an hour is simply missed in the Spring.

Did it ever cause problems or confusion?

It really is as simple as writing. "All times now in BST" under the last entry before the clocks change.

But generally if you had anything safety critical you would ensure a clear understanding regarding the clock change. or simply avoid doing some activities until after 2am

 

[Magdalia]

How was potential confusion avoided when the hour went back in autumn?

For a signal box there was an entry in the train register. An example that I have says:

"clock put back 1hr from 3.0am to 2.0am"

and there were train times in the register between 2.0am and 3.0am both before and after.

For most of railway history times were not on the 24 hour clock, there was separate am and pm each day.

 

[izvor]

Did it ever cause problems or confusion?

Haha, well it certainly did when I did a rail replacement job one October night at Gatwick Airport.

Firstly it transpired that the airport, the railway and my company all changed their time at different hours. Not sure why, it's set out clearly when the clocks should go back (0200-0100, but I think rail and/or bus choose a later hour, maybe to avoid night shift payments). On top of that, many of the clocks around terminal and station were not changed at the correct time anyway. I have a memory of some Germans arriving to find various clocks displaying different times, and the departure boards not making much sense either, and not being terribly impressed.

Furthermore the schedule I was given took no account of the extra hour, meaning I had to conjure up additional trips to maintain the headway during the "missing hour".

Clocks go back - great - an extra hour's sleep. Not when you're working a night shift! I didn't fall for that one again.

 

[Taunton]

In the 1930s the French railways paid a bonus to drivers for recovery of lost time (I can just imagine the British reaction to this nowadays!). The key shift they looked forward to was the Spring clock change on overnight sleeping car trains, which became an hour late. Apparently very little sleep was achieved that night as the train was driven at maximum warp factor to regain so many minutes.

I did in more recent times have involvement with the payroll of a business with aspects operating 24x7. When clocks went forward we still paid a normal shift. When they went back we paid an hour's overtime. Advantage for the staff both ways!

 

[Belperpete]

The Southern Region used a master clock system for most of the public clocks on the region. The master clock in the telephone exchange at Waterloo would produce a pulse every thirty seconds, which was distributed to all the sub exchanges around the region, which then distributed it via a number of clock circuits to all the clocks. These clocks were quite distinctive, as the minute hand stepped every half minute with a clunk. Rather than a traditional clockwork clock, where the minute hand moves gradually.

When clocks with second hands were introduced, these used mains power, but only to drive the seconds hand - the minute and hour hands were still driven by the pulses. If you looked at these clocks closely, the second hand would get to the 12 o'clock position, and pause briefly until the minute hand clunked round.

When the clocks were due to go back, the clock pulses from Waterloo were stopped for an hour. I understand that at one time this was done by simply putting a bit of paper between the appropriate relay contacts. When the clocks were due to go forward, the tech would just keep pressing the relay to generate extra pulses.

The master clocks were impressive pendulum clocks. I think Waterloo had main and backup master clocks. In addition, each local exchange had its own backup master clock, that could be switched in if the pulses from Waterloo were lost. Some bright spark had the idea of doing this automatically, with a circuit that monitored the incoming pulses, and automatically switched to the local master clock. Unfortunately, when the clocks were due to go back, and the tech at Waterloo stopped the pulses for an hour, this circuit then promptly switched over to the local master, and the clocks kept going!

 

[Falcon1200]

it's set out clearly when the clocks should go back (0200-0100, but I think rail and/or bus choose a later hour, maybe to avoid night shift payments).

AFAIK the railway always changed clocks at the specified time, ie 0100/0200, and this was laid down in the Weekly Operating Notice. If there was no night shift staff would not be called out specially to adjust the clocks, the first shift after the change would do that.

In March night shift staff had the benefit of a 60 minute shorter shift, but in October a 60 minute longer one, which in my case resulted in a 13 hour turn! And it rarely worked out that the same people were night shift for both clock changes.

 

[Buzby]

ordeal as it is with digital clocks which will only adjust forwards.

Most of mine have an Up/Down button so still a single press.

 

[Rescars]

The Southern Region used a master clock system for most of the public clocks on the region. The master clock in the telephone exchange at Waterloo would produce a pulse every thirty seconds, which was distributed to all the sub exchanges around the region, which then distributed it via a number of clock circuits to all the clocks. These clocks were quite distinctive, as the minute hand stepped every half minute with a clunk. Rather than a traditional clockwork clock, where the minute hand moves gradually.

When clocks with second hands were introduced, these used mains power, but only to drive the seconds hand - the minute and hour hands were still driven by the pulses. If you looked at these clocks closely, the second hand would get to the 12 o'clock position, and pause briefly until the minute hand clunked round.

When the clocks were due to go back, the clock pulses from Waterloo were stopped for an hour. I understand that at one time this was done by simply putting a bit of paper between the appropriate relay contacts. When the clocks were due to go forward, the tech would just keep pressing the relay to generate extra pulses.

The master clocks were impressive pendulum clocks. I think Waterloo had main and backup master clocks. In addition, each local exchange had its own backup master clock, that could be switched in if the pulses from Waterloo were lost. Some bright spark had the idea of doing this automatically, with a circuit that monitored the incoming pulses, and automatically switched to the local master clock. Unfortunately, when the clocks were due to go back, and the tech at Waterloo stopped the pulses for an hour, this circuit then promptly switched over to the local master, and the clocks kept going!

Thank you for this explanation. I have a very distant memory of clocks which clunked!

I see that Rule 33 in the 1950 Rulebook tells of a daily time signal sent out so that most stations and signal boxes could check their clocks. Does anyone know when this ceased (assuming that it has)? There would appear to have been some locations where this didn't work, so the Rule was to "obtain the time from the Guard of the first stopping train commencing its journey after 10.0 am".

The daily time signal appears to have a long history - maybe as old as the electric telegraph. The 1904 GWR Rulebook says that the time is telegraphed to principal stations, whilst elsewhere it seems reliance was placed on the Guard of the first stopper after 10 am to provided the right time to the Station-master. There is a note that "Block Signal-boxes (sic) not provided with Speaking Instruments will be supplied with the time in accordance with Block Telegraph Regulations". Does anyone know what this means? Was there a special bell code perhaps?

 

[Gloster]

Thank you for this explanation. I have a very distant memory of clocks which clunked!

I see that Rule 33 in the 1950 Rulebook tells of a daily time signal sent out so that most stations and signal boxes could check their clocks. Does anyone know when this ceased (assuming that it has)? There would appear to have been some locations where this didn't work, so the Rule was to "obtain the time from the Guard of the first stopping train commencing its journey after 10.0 am".

The daily time signal appears to have a long history - maybe as old as the electric telegraph. The 1904 GWR Rulebook says that the time is telegraphed to principal stations, whilst elsewhere it seems reliance was placed on the Guard of the first stopper after 10 am to provided the right time to the Station-master. There is a note that "Block Signal-boxes (sic) not provided with Speaking Instruments will be supplied with the time in accordance with Block Telegraph Regulations". Does anyone know what this means? Was there a special bell code perhaps?

In 1936 the GWR used the code 8-5-5 as a Time Signal. Presumably at an agreed time, probably immediately after the one given over the circuit ‘phones, Box A would send the signal to Box B.

 

[Belperpete]

In 1936 the GWR used the code 8-5-5 as a Time Signal. Presumably at an agreed time, probably immediately after the one given over the circuit ‘phones, Box A would send the signal to Box B.

The concept of the time signal being sent out seems a simple concept, until you start to consider the practicalities.

By the time box B had then sent it on to box C, and box C sent it on to box D, and so on, there would presumably have been quite a time delay. Remember that there were a lot of signal boxes around in mechanical days, with even modest stations having boxes at both ends, and intermediate boxes between stations. And at junctions, the signalman might have to repeat it to more than one box. Even if every signalman was stood waiting to start sending it on as soon as he received the first beat, the delay would still build up.

If each box forwarded it at an agreed time, say A to B at 10:00, B to C at 10:01, C to D at 10:02, and so on, then this would surely need to be specified somewhere, presumably in the box instructions, for relief men to know what time it was supposed to be received and sent on at each box.

I am not sure that "speaking instruments" necessarily meant telephones. The "speaking telegraph" was the same as the public telegraph that was used to transmit messages using multiple needles, as opposed to the single-needle block telegraph used for signalling purposes. Signalbox "circuit phones" tended to be fairly local in the area they covered, as with circuits carried on overhead pole routes, the longer the circuit and the more telephones connected to it, the noisier it became. Whereas the telegraph could cover quite long distances, even with multiple receiver stations in circuit.

I have never seen a signalbox with a speaking telegraph, as well as the block telegraphs, but I am sure that there has been mention on here of boxes so equipped so that details of service alterations could be sent out to multiple boxes at once. I suspect that in most places, the telex and the fax replaced the speaking telegraph. However, they wouldn't be much use for transmitting a time signal.

 

[contrex]

Not exactly about clock signals, but I remember reading somewhere that French train drivers used to get a punctuality bonus for every minute early that they arrived at their destination, provided they kept to speed limits, etc, (they had Flaman tachygraphes ferroviaires before 1900) and that it was enshrined in tradition that they got a whole hour of 'early money' if their run ended after the clocks had gone back. But not a corresponding penalty when they went forward!

 

[Gloster]

Recollection and memories of odd comments from those who had been on the railway for years is that the time signal was sent over the circuit ‘phones by the railway telephone exchange. There were plenty of these exchanges at one time: I believe that, for example, there were exchanges at Westbury, Taunton, Exeter, Newton Abbot and Plymouth. Some of the circuit lines were quite long: there was one that, if I remember correctly, ran from Westbury to Maiden Newton and had previously continued to Dorchester and possibly once to Weymouth.

My understanding of the 8-5-5 bell signal is that it was a relic of the days when not all boxes had ‘phones and was only used in those cases. If a box had a ‘phone it received the time signal in the normal way.

 

[John Webb]

The Southern Region used a master clock system for most of the public clocks on the region. The master clock in the telephone exchange at Waterloo would produce a pulse every thirty seconds, which was distributed to all the sub exchanges around the region, which then distributed it via a number of clock circuits to all the clocks. These clocks were quite distinctive, as the minute hand stepped every half minute with a clunk. Rather than a traditional clockwork clock, where the minute hand moves gradually.

When clocks with second hands were introduced, these used mains power, but only to drive the seconds hand - the minute and hour hands were still driven by the pulses. If you looked at these clocks closely, the second hand would get to the 12 o'clock position, and pause briefly until the minute hand clunked round.

When the clocks were due to go back, the clock pulses from Waterloo were stopped for an hour. I understand that at one time this was done by simply putting a bit of paper between the appropriate relay contacts. When the clocks were due to go forward, the tech would just keep pressing the relay to generate extra pulses.

The master clocks were impressive pendulum clocks. I think Waterloo had main and backup master clocks. In addition, each local exchange had its own backup master clock, that could be switched in if the pulses from Waterloo were lost. Some bright spark had the idea of doing this automatically, with a circuit that monitored the incoming pulses, and automatically switched to the local master clock. Unfortunately, when the clocks were due to go back, and the tech at Waterloo stopped the pulses for an hour, this circuit then promptly switched over to the local master, and the clocks kept going!

These clocks were the Gent's 'Pulsomatic' system, I think it was called. We've a master clock working at St Alban's South, which came from the signal works at Crewe. Curiously the NRM at York has the former master clock from St. Albans City station! But that wasn't working when I last saw it.

 

[Belperpete]

Recollection and memories of odd comments from those who had been on the railway for years is that the time signal was sent over the circuit ‘phones by the railway telephone exchange. There were plenty of these exchanges at one time: I believe that, for example, there were exchanges at Westbury, Taunton, Exeter, Newton Abbot and Plymouth.

But that leads to the question: where did all these exchanges get their time signal from?

Some of the circuit lines were quite long: there was one that, if I remember correctly, ran from Westbury to Maiden Newton and had previously continued to Dorchester and possibly once to Weymouth.

Agreed that some circuits were relatively long. But there wouldn't have been a circuit phone from say Paddington to Penzance. If you wanted to make a long distance call, it might involve one or more exchanges daisy-chaining circuits together. With very bad call quality. Usual practice was to get the exchange to pass your message on. But then it was rare that a signalman needed to make a long distance call.

 

[The exile]

When clocks with second hands were introduced, these used mains power, but only to drive the seconds hand - the minute and hour hands were still driven by the pulses. If you looked at these clocks closely, the second hand would get to the 12 o'clock position, and pause briefly until the minute hand clunked round.

Like the classic DB clock and presumably for the same reason. I’ve often wondered why they did that.

 

[Merle Haggard]

It seems that the 807's computer hasn't quite got the hang of the concept of changing clocks In the Spring.

Travelling on the 13.48 down arrival at New Street (at 13.58, which the screen showed as 'on time', but that's another matter) the list of departures started at 14.52 and continued past 15.00
It seems to me that the + 1 hour has been added incorrectly at an intermediate stage of the enquiry routine.
There were plenty of trains leaving between 13.58 and 14.52.

 

[Gloster]

But that leads to the question: where did all these exchanges get their time signal from?

I do not know, but unless there was some local non-railway source, I presume that it was one of two methods. Either each exchange rang somewhere like Paddington, which had got their time from a reliable source, and then they (the exchange) carefully corrected their master clock in the exchange. Or from the first exchange each exchange rang the next down the line. (Or they jumped a few: Paddington told Swindon, which told several including Westbury and Bristol, with the last telling Taunton, etc.; meanwhile Paddington told Exeter, which told Newton Abbot, etc.)

It wouldn’t have been difficult: “Morning, Joe, Swindon here for the time check. It is coming up to 8.47.…it is 8.47…now.)