Trains that passed in the night ... how'd they do that?
May 27, 2013 5:49 PM Subscribe
During the Civil War era, what kind of signals guided intercity trains traveling at night?
Around 1865, in the dark, what signalling systems did railroads use to indicate traffic or track conditions ahead? A lonely switchman with a lantern? A light on a fixed mast by the track?
Around 1865, in the dark, what signalling systems did railroads use to indicate traffic or track conditions ahead? A lonely switchman with a lantern? A light on a fixed mast by the track?
In 1865 during the day they are most likely to have been ball signals, a ball on a rope that was raised or lowered. There might have been some very early semaphore.
At night if trains had to run then possibly smash boards. These were wooden boards that would be swung out blocking the track.
Generally there was not high density signaling indicating conditions or traffic, it would operate on an as absolute block system where the signal man would have responsibility for a section of track and would not let trains enter until they received word that it was clear.
For bi directional operation it would be token block which involved giving train drivers a physical token, like a baton, which allowed then into the section
posted by Just this guy, y'know at 7:13 PM on May 27, 2013
At night if trains had to run then possibly smash boards. These were wooden boards that would be swung out blocking the track.
Generally there was not high density signaling indicating conditions or traffic, it would operate on an as absolute block system where the signal man would have responsibility for a section of track and would not let trains enter until they received word that it was clear.
For bi directional operation it would be token block which involved giving train drivers a physical token, like a baton, which allowed then into the section
posted by Just this guy, y'know at 7:13 PM on May 27, 2013
Don't forget the telegraph. I suspect a train probably wouldn't leave one station until the next station was clear.
posted by gjc at 7:33 PM on May 27, 2013
posted by gjc at 7:33 PM on May 27, 2013
It seems that proper block signaling was only just coming in in Britain in the 1850s the us probably would not have used it in 1865.
It actually seems that trains worked on time tables with orders and modifications being transmitted by telegraph to local dispatchers. So a night train in the us in 1865 wouldn't have any traffic regulation signals at all.
If there was a line blockage that would probably be shown with a red filtered oil lamp and track detonators (small explosive discs that make a loud noise if a train passes them)
posted by Just this guy, y'know at 7:42 PM on May 27, 2013
It actually seems that trains worked on time tables with orders and modifications being transmitted by telegraph to local dispatchers. So a night train in the us in 1865 wouldn't have any traffic regulation signals at all.
If there was a line blockage that would probably be shown with a red filtered oil lamp and track detonators (small explosive discs that make a loud noise if a train passes them)
posted by Just this guy, y'know at 7:42 PM on May 27, 2013
Though this isn't exactly what you're asking, there's a very good description of a how train crew of that era communicated with stations and various other entities in Midnight Rising.
http://www.amazon.com/gp/aw/d/B00AZ8C8PM/ref=redir_mdp_mobile
Of course, that's what happens when it all goes very wrong, but you get a good sense of how important telegraph lines were, and IIRC it also gets into how (if?) the tracks were lit. (I vaguely recall they weren't, but someone might walk out with a lantern if need be. The part I remember is how the passengers communicated with people along the train's route, by throwing little notes out the windows, like 19th c. Twitter.) Anyway, there might be some of the type of info you're looking for in that account.
posted by DestinationUnknown at 8:37 PM on May 27, 2013
http://www.amazon.com/gp/aw/d/B00AZ8C8PM/ref=redir_mdp_mobile
Of course, that's what happens when it all goes very wrong, but you get a good sense of how important telegraph lines were, and IIRC it also gets into how (if?) the tracks were lit. (I vaguely recall they weren't, but someone might walk out with a lantern if need be. The part I remember is how the passengers communicated with people along the train's route, by throwing little notes out the windows, like 19th c. Twitter.) Anyway, there might be some of the type of info you're looking for in that account.
posted by DestinationUnknown at 8:37 PM on May 27, 2013
When trains departed a yard they picked up "train orders" on their way out, which define a set schedule that the train must meet. The orders specify where they have to wait for passing / overtaking trains, etc., and thus prevent collisions if properly created and executed.
The WP page on train order operation is worth a read.
One note about train orders is that prior to radio, updates or continuations of train orders, such as might be received periodically by a long-distance train, would be sent by telegraph to a station and then someone from the station would need to pass them along to the train crew. In many cases, the train didn't stop.
The man on the ground — and I think this was in place by the Civil War, although some railroads might have been using an older system that used bamboo hoops — held a device called an "order fork", which held the train orders tied to a loop of string. The engineer would lean out the cab and put his arm through the end of the Y of the order fork, snagging the string and the orders. I have seen historical-preservation groups staffed by old railroad guys do this successfully once, and it's quite a thing to watch.
This system, with train orders being passed to stations by telegraph and then passed to trains via order forks, was widespread in the US until the introduction of portable radios which basically obviated the whole thing (including the necessity of having to stand fairly close to a locomotive as it blew past you).
The downside to the whole train order system is that it's very inflexible. If something goes wrong and a train falls off its appointed schedule, other trains might have to wait for it to pick up the slack before proceeding. Modern DTC systems are much better in this regard.
posted by Kadin2048 at 8:38 PM on May 27, 2013 [1 favorite]
The WP page on train order operation is worth a read.
One note about train orders is that prior to radio, updates or continuations of train orders, such as might be received periodically by a long-distance train, would be sent by telegraph to a station and then someone from the station would need to pass them along to the train crew. In many cases, the train didn't stop.
The man on the ground — and I think this was in place by the Civil War, although some railroads might have been using an older system that used bamboo hoops — held a device called an "order fork", which held the train orders tied to a loop of string. The engineer would lean out the cab and put his arm through the end of the Y of the order fork, snagging the string and the orders. I have seen historical-preservation groups staffed by old railroad guys do this successfully once, and it's quite a thing to watch.
This system, with train orders being passed to stations by telegraph and then passed to trains via order forks, was widespread in the US until the introduction of portable radios which basically obviated the whole thing (including the necessity of having to stand fairly close to a locomotive as it blew past you).
The downside to the whole train order system is that it's very inflexible. If something goes wrong and a train falls off its appointed schedule, other trains might have to wait for it to pick up the slack before proceeding. Modern DTC systems are much better in this regard.
posted by Kadin2048 at 8:38 PM on May 27, 2013 [1 favorite]
Kadin2048: If something goes wrong and a train falls off its appointed schedule, other trains might have to wait for it to pick up the slack before proceeding. Modern DTC systems are much better in this regard.Do you mean DTG (Distance To Go)? Can't find what DTC could mean.
posted by IAmBroom at 11:36 PM on May 27, 2013
I'm at work so I can't search youtube - but there is great video on youtube called 'rail crash' that is about an hour long, telling the history of British Rail Signalling systems. From block signalling, to the telegraph and onto to track circuiting.
It's not the civil war, but the systems would have been similar.
It's actually a little hard to find on youtube. So if I get the chance later I'll chase down the link.
posted by Burgatron at 11:40 PM on May 27, 2013
It's not the civil war, but the systems would have been similar.
It's actually a little hard to find on youtube. So if I get the chance later I'll chase down the link.
posted by Burgatron at 11:40 PM on May 27, 2013
DTC = Direct Traffic Control, which is one version of CTC, or Centralized Traffic Control.
posted by dhartung at 2:32 AM on May 28, 2013 [1 favorite]
posted by dhartung at 2:32 AM on May 28, 2013 [1 favorite]
I suspect that like early signalling in the UK they would have used a staff. The loco can't proceed unless it has the staff. info
posted by Mario Speedwagon at 6:38 AM on May 28, 2013
posted by Mario Speedwagon at 6:38 AM on May 28, 2013
Yes I meant Direct Traffic Control, which is basically where you have a dispatcher communicating directly (via radio) with the train crews, and telling them to move from point X to point Y along a track (typically specified in blocks with names or letter codes), pull onto siding Z, wait for another train, proceed ... etc. The dispatcher has responsibility over a region of track and trains get handed off from one dispatcher to another as they move along.
DTC is still used by some smaller railroads, and gets used by even mid-sized ones in and around yard areas. It creates a lot of radio traffic, and if you have a scanner you can tell pretty easily what is going on. (It sounds not totally dissimilar to air traffic control radio chatter, although more verbose.)
It is different from CTC in that most CTC systems have as a defining characteristic some way of actually determining a train's position and communicating that to the dispatcher/controller, and then the dispatcher controls automatic signals which the train crew obey. CTC is actually older than DTC and predates portable radios, but the implementation costs are higher, so a lot of railroads went from the traditional train order / timetable system to DTC, and are only now moving to CTC.
It's probably unnecessary to say this, but train signalling is a really deep rabbit hole if you are interested in such things. There was a lot of really cool stuff done in the 1920s and 30s on the big railroads, esp. the Pennsylvania Railroad (which was always a tech leader) that really pushed the limits of what was available at the time. E.g. in-cab signaling using pulse-code modulation using the tracks as an inductive loop to transmit a 60Hz (later 100Hz) signal to a receiver in the locomotive. This system is still in use on the East Coast, including by Amtrak on the NEC, today.
We're getting away from OP's original question, but hopefully it's relevant enough to be interesting.
posted by Kadin2048 at 11:55 AM on May 28, 2013 [1 favorite]
DTC is still used by some smaller railroads, and gets used by even mid-sized ones in and around yard areas. It creates a lot of radio traffic, and if you have a scanner you can tell pretty easily what is going on. (It sounds not totally dissimilar to air traffic control radio chatter, although more verbose.)
It is different from CTC in that most CTC systems have as a defining characteristic some way of actually determining a train's position and communicating that to the dispatcher/controller, and then the dispatcher controls automatic signals which the train crew obey. CTC is actually older than DTC and predates portable radios, but the implementation costs are higher, so a lot of railroads went from the traditional train order / timetable system to DTC, and are only now moving to CTC.
It's probably unnecessary to say this, but train signalling is a really deep rabbit hole if you are interested in such things. There was a lot of really cool stuff done in the 1920s and 30s on the big railroads, esp. the Pennsylvania Railroad (which was always a tech leader) that really pushed the limits of what was available at the time. E.g. in-cab signaling using pulse-code modulation using the tracks as an inductive loop to transmit a 60Hz (later 100Hz) signal to a receiver in the locomotive. This system is still in use on the East Coast, including by Amtrak on the NEC, today.
We're getting away from OP's original question, but hopefully it's relevant enough to be interesting.
posted by Kadin2048 at 11:55 AM on May 28, 2013 [1 favorite]
Response by poster: Yes, the convo has gotten away from the question. Radios, for example, were not used in 1865. But I agree, it is interesting.
posted by LonnieK at 8:00 AM on May 29, 2013
posted by LonnieK at 8:00 AM on May 29, 2013
This thread is closed to new comments.
early train signals
posted by Tandem Affinity at 7:10 PM on May 27, 2013