|
Post by mcdrye on Nov 12, 2006 22:13:47 GMT
Just a random question, On my daily travels from Bank to Angel I notice the side of the train of which the platform is, changes. Whilst this would makes sense if only one station was an 'island' platform, both stations, including Old Street and Moorgate are.
I just wondered how the trains cross over? each other between Bank and Moorgate because its not noticed when you are on the train.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 12, 2006 22:23:08 GMT
When CSLR sees this thread he will put forth another excellent monologue on the history of this part of the Bank Branch, but to make the long story short, the tunnels 'roll over' each other south of Moorgate, and 'roll over' each other again near Borough. This was done because this part of the Northern originally terminated at King William Street, and to reach this terminus, the tunnels 'rolled over' to increase the radii of the curves required.
The Central Line does something similar west of Shepherd's Bush.
|
|
|
Post by mandgc on Nov 12, 2006 22:37:27 GMT
When the C&SLR was extended to Moorgate in 1900 and King William Street station was closed, as the lines at the junction were one above the other, it was convenient to make the lines through the new London Bridge station 'Right hand Running'. Normal left hand running was resumed between Bank and Moorgate stations. ( Possibly the presence of the River above and the old King William Street line alongside made it impossible to change back before passing Bank station)
|
|
|
Post by CSLR on Nov 13, 2006 0:06:24 GMT
You are all doing pretty well so far and getting reasonably warm with your answers. As TOK suspects, the real story is a little stranger than most people might imagine. Keep the theories coming and I will fill in the missing details tomorrow night.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 13, 2006 0:23:08 GMT
The story is no stranger than the C&SLR's original choice to use cable traction, thus causing them to build a curve with an impossibly small radius on a 1 in 40 gradient (!!!). The traction system was so overloaded as a result that heavy trains unable to ascend this sharp curve into King William Street would often roll back and try again! There is also the fact that the point where the original route to King William Street diverges from the current route is in fact to the southwest of the existing London Bridge station, and that when opened the C&SLR did not have a station there, contributing to the oddball nature of this portion of the line. When the route was diverted via London Bridge and extended to Moorgate Street these tunnels were blocked off but left otherwise intact until 1996, when the southbound tunnel was severed by Jubilee Line-related construction works. The northbound tunnel is IIRC still continuous and intact, and used for ventilation of the Jubilee. But to roast this thread alive, I should of course mention that the whole reason why the C&SLR built such a sharp curve was because they needed to stay under the public roadways in the City; otherwise they would have had to purchase every single building that they tunneled beneath. IIRC the original northern rollover was either very close to or under the Thames; the original southern rollover is of course still in use. Did I also mention that King William Street was rebuilt with a single bay platform to lessen the agony felt by the traction system after a loco+train went up the 1 in 40 into the station?
|
|
|
Post by CSLR on Nov 13, 2006 0:46:05 GMT
The story is no stranger than the C&SLR's original choice to use cable traction. I think you may find that it is a lot stranger than that Also the choice of cable traction was vital. If they had not chosen that when they did, the line would almost certainly not have been constructed at that time. Greathead's deal with the Patent Cable Tramway Corp effectively bankrolled the project. ...the whole reason why the C&SLR built such a sharp curve was because they needed to stay under the public roadways in the City Perfectly true and a contributory factor in the wrong line running story. But which section of road caused the problem?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 13, 2006 0:54:06 GMT
The story is no stranger than the C&SLR's original choice to use cable traction. I think you may find that it is a lot stranger than that Also the choice of cable traction was vital. If they had not chosen that when they did, the line would almost certainly not have been constructed at that time. Greathead's deal with the Patent Cable Tramway Corp effectively bankrolled the project. Interesting. ...the whole reason why the C&SLR built such a sharp curve was because they needed to stay under the public roadways in the City Perfectly true and a contributory factor in the wrong line running story. But which section of road caused the problem? Swan Lane and Arthur Street. The station tunnel at King William Street points east towards Monument Street.
|
|
|
Post by CSLR on Nov 13, 2006 1:06:34 GMT
But which section of road caused the problem? TheOneKEA replied:[/b] Correct. But why did thats cause wrong line running?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 13, 2006 1:12:39 GMT
Because the near-90 degree turn underneath these two roads could not be duplicated for both tunnels. Therefore the n/b tunnel made the sharp curve, while the s/b tunnel passed beneath it and curved slightly more gently along the road alignment, finishing up north of the n/b tunnel. The point where the s/b tunnel crosses beneath the n/b tunnel is the original rollover.
ISTR a website where pictures of the horrendously sharp curve in one of the tunnels could be seen, along with the stalactites formed by leakage through the cast iron tunnel segments.
|
|
|
Post by CSLR on Nov 13, 2006 21:36:50 GMT
When Greathead started constructing the C&SLR, he had to face a belief expressed by several prominent engineers that London Bridge would fall down if he tunnelled too close to it. Greathead therefore decided to build the controversial under-river section first. He started work by sinking a shaft in the river just off of Swan Lane, from where he planned to start construction of the tunnels one above the other. This arrangement was necessary because there was no statuatory authority to pass beneath buildings. Swan Lane was the only suitable road that ran down to the north bank of the river, but was not wide enough to allow the tunnels to run side-by-side, so they had to be stacked on top of each other at that point. As a bonus, it saved him the problem of having to sink two shafts in the river. From Old Swan Shaft, he proposed to build his tunnels out beneath the Thames, knowing that his two biggest challenges were:- 1. Constructing the closer of the two tunnels to London Bridge (because of the danger of damaging the bridge). 2. Constructing a tunnel too close to the bed of the river (because of the danger of the river breaking into the works, as experienced by Brunel in the Thames Tunnel). To get both of these issues out of the way, he built the upper tunnel first (starting October 1886) and dropped it down to pass beneath the deepest point in the river bed. He also decided to make this the closest of the two tunnels to London Bridge. This meant that the most difficult part of the construction was the first to be completed. When the second tunnel was started in February 1887, it had to fit into the space between the first tunnel and the eastern limit of deviation (the ‘limit of deviation’ is a legal boundary approved by parliament beyond which the railway may not be constructed). With the under-river tunnels complete, Greathead turned round and prepared to build the line towards King William Street. After passing one above the other along Swan Lane, the lines ran along Arthur Street West and had to align themselves side-by-side very quickly before entering King William Street station. This meant that the lower tunnel had a steeper climb into the station than the higher one. The company chairman, Charles Grey Mott, did not favour cable traction and was already considering some form of powered locomotion, so it did not make sense to create an approach gradient that was steeper than necessary. It was therefore decided to make the higher tunnel the up (northbound) line, as this would give a more gentle - though still very steep - climb for trains entering King William Street station. The lower tunnel, with the crippling 1 in 14 rise became the down (southbound) line. In the end, that was exactly the right decision, as the electric locomotives had enough trouble with the 1 in 29 - an even steeper climb would have been virtually impossible for them. So, by becoming the up line, the higher tunnel created a dilemma. Because it had been constructed closest to London Bridge when passing under the Thames, the running direction was the reverse of normal. To put the lines back in the right place, they were finally reversed by passing the down line beneath the up line between Borough and Elephant & Castle stations. Few staff and passengers realise that Borough is wrong way working, because this fact is totally concealed from them by the split level layout. When the extension to Moorgate Street was built, it was decided to flip the lines back again. After breaking away from the old line north of the Borough, the tunnels had to drop down to pass beneath the original tubes. In order to keep the gradients under control, it was not possible to cross the lines back before London Bridge station. After London Bridge, the lines tackled the river and had to remain at a deep level to pass beneath the brick tunnel of King William Street station. After that there was not enough space to flip them over before they entered Bank station. The lines therefore crossed back between Bank and Moorgate Street.
A couple of points:- 1. Greathead was very much a seat-of-the-pants engineer and appears not always to have worked things out fully in advance. This is clearly demonstrated by his evidence to parliamentary committees when applying for authority to construct a line. When asked how he was going to do something, he appeared to make things up only to change them after giving the matter some thought. This does not mean that he was a bad engineer, it seems just to have been a case of, ‘We will solve that when we get to it’. That quote, incidentally, was not from the mouth of Greathead, just in case anyone reads this and thinks of attributing it to him (one of the problems of the internet!) 2. The C&SLR always planned to have a station at London Bridge, but it was never built on the original line due to a dispute with a main line company over the provision of a covered way. 3. The original layout at King William Street was a single track terminus as necessitated by cable operation. This was later converted to a two-track island platform. Stockwell was built after the decision was made to use electricity and so always had a two-track island platform layout. 4. Although parliament would not pass an Act allowing the C&SLR wayleave beneath buildings, the company reached a private agreement with the owner of Hibernia Wharf to pass beneath a corner of their building. This was the only way to get the tracks back beneath a highway on the south side of the river. I do not think that anyone has ever pointed out that the tunnels actually diverge from their permitted line of deviation at this point and actually pass beneath a larger part of the building than the 'corner' that Greathead suggested.
|
|
Phil
In memoriam
RIP 23-Oct-2018
Posts: 9,473
|
Post by Phil on Nov 14, 2006 14:09:28 GMT
Oh CSLR - if only you'd been a member a year ago!!
We spent weeks (well, days anyway!) discussing the reasons for it and none of us could come up with a definitive answer!
Thanks indeed.
|
|
Colin
Advisor
My preserved fire engine!
Posts: 11,310
|
Post by Colin on Nov 15, 2006 2:39:44 GMT
Well that's confirmed something for me.... I always thought Bank was the wrong way round - now I know it is, and the reason why
|
|
Phil
In memoriam
RIP 23-Oct-2018
Posts: 9,473
|
Post by Phil on Nov 15, 2006 7:14:27 GMT
And, to make our joy complete, I suppose nobody has done a plan/drawing of the route showing the exact orientation of the two lines in the various locations (or indeed along the route)?? Please?
|
|
|
Post by CSLR on Nov 15, 2006 12:21:33 GMT
And, to make our joy complete, I suppose nobody has done a plan/drawing of the route showing the exact orientation of the two lines in the various locations (or indeed along the route)?? Please? I can probably put some plans up, if you will bear with me for a couple of days. I will try to digitise what I have, but it will take a little work to make them readable in a smaller scale.
|
|
Phil
In memoriam
RIP 23-Oct-2018
Posts: 9,473
|
Post by Phil on Nov 15, 2006 12:44:40 GMT
Thanks. Eagerly awaited!
|
|
|
Post by mcdrye on Nov 15, 2006 16:48:52 GMT
Wow what a great reply from CSLR! I can't wait for the plans! Which tunnel goes above the other though?
On a side note seeming as we're speaking of the Bank branch, why does no-one take interest in the echoing cavern of City Road as the train passes it? Would this station ever be reopened?
|
|
|
Post by Tubeboy on Nov 15, 2006 17:40:21 GMT
Unlikely, Old St is not far away. Several bus routes ply between Angel and Old St. Most importantly, is it really needed?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 15, 2006 17:59:08 GMT
I'd say City Road would make a useful addition, Old Street is quite a slog away, and Angel is uphill and round the corner... Theres a lot of flats around the station, but is served rather well with buses... would be nice to see it re-opened, bit I guess on the same vein as York road, costs would be astronomical...
|
|
|
Post by mcdrye on Nov 15, 2006 18:10:03 GMT
Whilst on the tube, Angel seems closer to City Road than Old Street. Do you mean surface building wise?
It seems on a busy peak morning, a lot of passengers get off at Old Street, then nearly the rest of the train get off at Angel. Maybe an extra station would help congestion but on the other hand more people might try and get on at Bank.
If it was reopened would escalators have to be built to comply with law or are only working lifts required?
This is what confuses me with Angel, why in the 1990s when it was reconstructed, allowed to have escalator only operation, why not keep the lifts open as well for disabled access?
|
|
|
Post by Tubeboy on Nov 15, 2006 18:21:40 GMT
Yep! Both ways!
I would imagine LU are kicking themselves for not installing an MIP lift. It obviously wasnt seen as a priority back in the early 90s.
Old St is very busy in the peaks. When I travel, most seem to alight at Kings X.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 15, 2006 18:29:36 GMT
The thing with opening extra stations in between existing ones is that it increases journey times for all passenger that travel beyond that station. Just opening one to have an extra station is not very wise. There has to be a significant demand to outweigh the negative influence of adding a station. (I would love the closure of all but the two stations I use on my beloved Central Line ;D) Regarding Angel, look at this image. Angel is so deep it would need two separate surface buildings to regain lift access. They had to move the surface entrance rather a lot to install escalators.
|
|
|
Post by mcdrye on Nov 15, 2006 19:00:40 GMT
The old surface building still exists though, I walk past it everyday. If both were open, all that is needed is a quick walk (could be signposted) through Angel Square.
My dad works for Viacom (previously worked on the Connect project before being made redundant lol don't maime him) so he has access to plans. Ive seen an Angel one before made by Tube Lines. According to the plans, the old lower concourse still exists. The only thing that would be required for any access is to re add stairs. Defeating the object of course for wheelchair access.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 15, 2006 19:21:57 GMT
Not necessarily!
Hounslow West has got a wheelchair lift in one of its stairwells; if TfL can get away with having step-free access for wheelchair users only, they might be able to get away with it at Angel Islington as well.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Nov 15, 2006 21:36:52 GMT
Anyone remember the old Wadsworth lifts at Angel. A blue moon occured if they were both working correctly!
|
|
|
Post by CSLR on Nov 15, 2006 21:38:12 GMT
Which tunnel goes above the other though? I am not sure which location you are querying; it is however easy to answer. Whenever two tunnel are aligned vertically on the C&SLR, the northbound tunnel is always on top of the southbound, thus:- The northbound is above the southbound at Old Swan Shaft. The northbound also passes over the southbound at Borough Road and again at Lothbury. Where old and new tunnels meet, the new tunnels pass beneath and parallel to the old ones from a point just north of Union Road to part way down the London Bridge station tunnels. They also pass at right angles beneath King William Street station, approximately half way along the platform. On a side note seeming as we're speaking of the Bank branch, why does no-one take interest in the echoing cavern of City Road as the train passes it? Would this station ever be reopened? The surface space is cramped and would have to be greatly extended. The layout of surrounding roads and buildings would probably fit in reasonably easily with a station development, but do not forget that this would be a total rebuild - including the station tunnels that would have to be extended in length to accommodate present day trains.
|
|
|
Post by angelislington on Nov 16, 2006 10:44:57 GMT
I can probably put some plans up, if you will bear with me for a couple of days. I will try to digitise what I have, but it will take a little work to make them readable in a smaller scale. yay, I'd love to see these! xx AngelIs
|
|
|
Post by CSLR on Nov 18, 2006 22:23:13 GMT
Here is a digitally enhanced and colour-coded image taken from an original plan. The darker colours represent the extension to Bank and Moorgate Street, the lighter colours are the original line. Everything else should now be self-explanatory.
|
|
Phil
In memoriam
RIP 23-Oct-2018
Posts: 9,473
|
Post by Phil on Nov 18, 2006 23:19:23 GMT
Yup, sure does clear up a lot of misunderstandings in a way a description never could. Thanks again.
|
|
|
Post by CSLR on Nov 19, 2006 13:43:44 GMT
I am now working on the Borough Junction / London Bridge area, but this requires a much wider plan in order to appreciate what is happening. It not so easy to follow if split into sections. As a result, I may have to host this off-site. I will experiment with one of the photo hosting sites. Any other suggestions?
|
|