What's a Chord?

[grahame]

Question asked of me ... worthy of a general reply as I think I know, but others may have a more techincal answer.

"A chord is a short length of railway connecting two other lines which cross, or forming a triangle where two other lines meet." - how does that sound?

Examples -

Bristol, from the Bath line to the Filton Abbey Wood line

Salisbury, from the line from Romsey to the line to Andover

Yeovil, from the Heart of Wessex line to the Salisbury = Exeter line (or is that too long to be considered a chord?)

Any other good examples?

Oh = and "The Lost Chord" is from Bradford North Junction to Bradford East Junction 

[eightf48544]

An excellent answer, so just a little extra to add.

A chord is usually of later construction than the lines it links. Thus the loop through Weston could be considered a chord as it was built after the B&E mainline and replaced the original terminal branch from the mainline.

There are a several classic wartime ones in your area Grahame, Tingley West curve and Westbury East chord plus Yeovil Pen Mill - Yeovil Jn all put in during the war. Reading New junction was also a wartime addition.

A classic GWR, in 1933, was at Little Somerford on the Badminton line where a link to the Malmesbury branch was put in and the part of the line from Dautsey on the Bristol ML  closed. You can still see the earth works if you are quick enough. Thus to travel from Calne to Malmesbury by train involved changes at Chippenham, Swindon and possibly Little Somerford. Legend has it that the connections weren't good so it could take several hours for a relatively short journey by road so the buses won.
 
BR did build several including the Avonmouth to Severn tunnel link at Filton in 1979. Thus making a cross with all four arms linked, I think it's unique in UK.

Other BR notables are the Hazel Grove chord facilitating the shutting of Manchester Central by allowing Hope Valley trains to use Picadilly and the Salford Crescent link to enable trains from Manchester Picadilly to join the L&Y to Wigan and Bolton. The Sussex Scot used to use the Salford chord. Thus it was 47 hauled from Brighton to  Preston before the electric came on.

One of my bigesst critisims of Beeching was that he didn't really investigate where new chords could be built to enable a train service to be run between towns but allowing the closure of duplicate parts of the network.

[G.Uard]

Examples -

Bristol, from the Bath line to the Filton Abbey Wood line

Salisbury, from the line from Romsey to the line to Andover

Yeovil, from the Heart of Wessex line to the Salisbury = Exeter line (or is that too long to be considered a chord?)

Any other good examples?

Filton (the triangular) Junction. Also plans afoot for a new chord linking the Chiltern Main Line to Brum, with the line to Oxford at Bicester

[Andy]

Another example of a chord is the one built at St Budeaux in Plymouth linking the LSWR line from Plymouth to Exeter via Okehampton and the GW line from Plymouth to Penzance.

[miniman]

Oh, so it's not a kind of Honda then? 

[Phil]

That certainly strikes achord, miniman....

[dog box]

Bristol from the Bath Line to The Filton line......which is from Feeder Bridge Junction to Dr Days Junction is more commonly known as The Rhubarb loop

[Sprog]

I've always known it as the 'Rhubarb Curve'

[chris from nailsea]

Well, I've seen it referred to elsewhere as either Rhubarb Loop (probable) or Rhubarb Curve (possible)?

Just doing a search now, though, produced this: (and my sincere respects to Stanley Martin):
http://flickr.com/photos/98587546@N00/2728741770/

[grahame]

Well, I've seen it referred to elsewhere as either Rhubarb Loop (probable) or Rhubarb Curve (possible)?

Just doing a search now, though, produced this: (and my sincere respects to Stanley Martin):
http://flickr.com/photos/98587546@N00/2728741770/

I'm puzzled - the commentary on that says "Empty stock, using the Rhubarb Loop to travel from St Philip's Marsh TMD to Temple Meads. Stan Martin was killed in the Ufton Nervet train crash in November 2004 through no fault of his own."   

My understanding is that the loop we've been talking about earlier is the one labelled "3" on this diagram, but the 125 is pictured at "4" as there's no logical route from St Philips Marsh ("2") to Temple Meads ("1") via "3".

[signalandtelegraph]

I agree, that's coming off St Phillips towards North Somerset Jct.  They sometimes use the Rhubarb loop to 'turn'  HST's going to Temple Meads from the depot.  Did the Rhubarb loop take its name from the pub next to it in Queen Anne Road or vice versa?

[willc]

Other BR notables are the Hazel Grove chord facilitating the shutting of Manchester Central by allowing Hope Valley trains to use Picadilly

No, this chord was built in 1986, long after Central closed, although it does link into the old Midland Railway route to Central. It was built to allow the Manchester-Sheffield fast trains to run via Stockport and offers a quicker journey than the former route via Romiley, which is still served by stopping trains.

[eightf48544]

I stand corrected should have checked my Cobb. Didn't realise Manchester Central closed as early as 1969.

Forgot it was probably around 64 when I last used it, there was an overnight train from Manchester Central to Marylebone via Fallowfield and the GC. Not sue if it went via the joint or Ayesbury as I was usually asleep.

It took a long time for BR get round to putting the chord in after clsoing . Now of course the Hope valley route is heavily used and overcrowded at peak times. Bring back Woodhead. Now if BR had built an East to South chord in Sheffield to allow Woodhead trains to serve Midland station you would probaly have 30 minute electric expresses between Manchester and Sheffield.

[dog box]

Well, I've seen it referred to elsewhere as either Rhubarb Loop (probable) or Rhubarb Curve (possible)?

Just doing a search now, though, produced this: (and my sincere respects to Stanley Martin):
http://flickr.com/photos/98587546@N00/2728741770/

I'm puzzled - the commentary on that says "Empty stock, using the Rhubarb Loop to travel from St Philip's Marsh TMD to Temple Meads. Stan Martin was killed in the Ufton Nervet train crash in November 2004 through no fault of his own."   

My understanding is that the loop we've been talking about earlier is the one labelled "3" on this diagram, but the 125 is pictured at "4" as there's no logical route from St Philips Marsh ("2") to Temple Meads ("1") via "3".



its a common working if sets need to be turned, travel from SPM via North Somerset junct, then via feeder bridge junct to dr days jnct via the rhubarb, change ends at Lawrence Hill Station then into BTM

[eightf48544]

According to R. A. Cooke link 3 was officially  called the Bristol Loop.

No. 4 has no name whilst 2 is the Bristol Relief line. Also there was loop to form a Bath facing triangle with 4. Thus trains from from the Frome and North Somerset Line could travel towards Bath and trains from Bath could avoid BTM via the Relief line.

I found an old Railway Annual with an article on Summer Satursdays at BTM in the fifties. A number of trains were booked Relief line and Bristol loop to avoid BTM.