"TheOneKEA" wrote in message
oups.com...

Brimstone wrote:

Interesting explanation snipped

So it's not a loop as in the case of Kennington or Heathrow loops
merely a
connection to the Piccadilly with a reversing facility?

Precisely.


So why is it called a loop?

In message , Brimstone
writes
So why is it called a loop?
A passing place on the railway is also called a loop.
--
Clive.

North to south reversals, where the train approaches Euston from
Bank, are not especially difficult ... North to south reversals,
where the train approaches from Camden and then returns to Camden,
might be a little more involved.

This wasn't a typo -- the first "North" means "northbound", while the
second one is in the sense of "north wind", right? grin
--
Mark Brader, Toronto | Any company large enough to have a research lab
| is large enough not to listen to it. --Alan Kay

In article . com,
TheOneKEA writes
Brimstone wrote:
Euston Loop? Can you tell us more about this?
Back in the days when the Bank branch platforms of the Northern Line at
[...]

Essentially correct. A diagram can be found on the Northern Line page of
CULG.

However, the presence of the
trailing crossover was deemed to be too useful to the line, so instead
of filling in the original NB tunnel north of the divergence, a
step-plate junction was built.

It would have been normal practice to build a step-plate junction in any
case, even if the old line was going to be abandoned. See London Bridge
and Angel for examples.

* - the other one was a planned connection between the Bakerloo and the
CCE&HR extension between Waterloo and Kennington; later it was
downgraded to a non-track connection, and then later forgotten. I could
be wrong about this though.

The original plan was for a Camden-style every-way-possible junction,
with both Northern and Bakerloo trains running to both Morden and
Camberwell. I'm not sure what you mean by "non-track connection"
(non-passenger connection, perhaps?) but I'd not heard that bit before.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

Clive D. W. Feather wrote:

However, the presence of the
trailing crossover was deemed to be too useful to the line, so
instead of filling in the original NB tunnel north of the
divergence, a step-plate junction was built.

It would have been normal practice to build a step-plate junction
in any case, even if the old line was going to be abandoned. See
London Bridge and Angel for examples.

True. I may have been a little unclear there; the step-plate junction
itself would have _always_ been built, but the tunnel beyond would have
been out of use and maybe filled in a short distance from the train.


* - the other one was a planned connection between the Bakerloo
and the CCE&HR extension between Waterloo and Kennington; later
it was downgraded to a non-track connection, and then later
forgotten. I could be wrong about this though.

The original plan was for a Camden-style every-way-possible junction,

with both Northern and Bakerloo trains running to both Morden and
Camberwell. I'm not sure what you mean by "non-track connection"
(non-passenger connection, perhaps?) but I'd not heard that bit
before.

Now that is something I'd not heard before! Do you have any more
information?

As for the non-track connection, an AET who works on the Bakerloo line
says that you can hear the Northern line when standing in the Lambeth
North scissors cavern; IIRC he speculated that the closeness of the two
lines would have made it easy for a foot connection of some kind. But
as I said, I could be wrong.

Mark Brader wrote:
North to south reversals, where the train approaches Euston from
Bank, are not especially difficult ... North to south reversals,
where the train approaches from Camden and then returns to Camden,
might be a little more involved.

This wasn't a typo -- the first "North" means "northbound", while the
second one is in the sense of "north wind", right? grin

You are indeed correct ;-)

On Fri, 4 Feb 2005, Mark Brader wrote:

North to south reversals, where the train approaches Euston from Bank,
are not especially difficult ... North to south reversals, where the
train approaches from Camden and then returns to Camden, might be a
little more involved.

This wasn't a typo -- the first "North" means "northbound", while the
second one is in the sense of "north wind", right? grin

Oh, i don't know - i think he meant what he said: "north to south
reversals where the train approaches from Camden and then returns to
Camden might be a little more involved" - rather considerably more
involved, i should think, since there'd have to be south to north
reversals on either side of it to get the directions right!

Of course, the wind interpretation can also be used to dramatically
simplify both north-to-south and south-to-north reversals, by interpreting
one of the directions conventionally and one as a wind direction, thus
turning the reversal into a simple straight run.



tom

--
That's no moon!

In article .com,
() wrote:

I've seen out of service trains reverse at Euston (Bank) but why would
they reverse an inservice train. At 7.30 this morning I crossed from
Camden CX branch to HB branch and the first train was going to Euston
only. No problems for me as I wanted the Victoria Line but this seemed
an odd thing to do.

Kevin


There are various reasons, one could have been that the train was late out
of depot and it was decided to reverse it S-N to make it correct time. It
is usually preferable to take passengers because at least it allows them
to get as far as Euston, where they can change as necessary.

If there's platform staff available to help detrain, then the delay
shouldn't be too much.

The other reversing move, N-S, allows people to be taken as far as Euston
SB platform, rather than detraining them at Kings Cross. However,
passengers are rarely taken into Euston this way because if the passengers
want to continue north, it is a long walk to the NB platforms. The train
may also be held in the Euston loop for some time, depending if it is
being held to its right time south.

also see:

http://www.romilepa.pwp.blueyonder.co.uk/ZTemp/

for odd bits of info. on things that have been mentioned in other parts of
this thread.

Roger
(my reader sometimes loses mail/newsgroup messages
- if you think you should have had a reply/comment,
please e-mail me again. Ta!)

In article .com,
(TheOneKEA) wrote:

Clive D. W. Feather wrote:

However, the presence of the
trailing crossover was deemed to be too useful to the line, so
instead of filling in the original NB tunnel north of the
divergence, a step-plate junction was built.

It would have been normal practice to build a step-plate junction
in any case, even if the old line was going to be abandoned. See
London Bridge and Angel for examples.

True. I may have been a little unclear there; the step-plate junction
itself would have _always_ been built, but the tunnel beyond would have
been out of use and maybe filled in a short distance from the train.

although this is normally the case, there are the odd exceptions, usually
due to geographical constraints

One example is at the north end of the SB diversion at London Bridge.
Here, the original NB tunnel was filled in and then the diversion dug
through it. There being insufficient clearance (I think it was something
to do with the foundations of the old London Bridge (as in bridge, not
station))in order to construct the step-plate. The southern end of the
diversion was a standard step-plate. The advantage of a step-plate
junction is that it can be built around the existing tunnel and trains can
continue to run during construction.
see:
http://www.romilepa.pwp.blueyonder.co.uk/ZTemp/
for a picture of the step-plate under construction

* - the other one was a planned connection between the Bakerloo
and the CCE&HR extension between Waterloo and Kennington; later
it was downgraded to a non-track connection, and then later
forgotten. I could be wrong about this though.

The original plan was for a Camden-style every-way-possible junction,

with both Northern and Bakerloo trains running to both Morden and
Camberwell. I'm not sure what you mean by "non-track connection"
(non-passenger connection, perhaps?) but I'd not heard that bit
before.

Now that is something I'd not heard before! Do you have any more
information?

As for the non-track connection, an AET who works on the Bakerloo line
says that you can hear the Northern line when standing in the Lambeth
North scissors cavern; IIRC he speculated that the closeness of the two
lines would have made it easy for a foot connection of some kind. But
as I said, I could be wrong.


The Northern Line also has a traction current feed from the Lambeth North
substation to the CX branch, so there's probably a tunnel between the two
anyway.

Roger

In article .com,
TheOneKEA writes
The original plan was for a Camden-style every-way-possible junction,
with both Northern and Bakerloo trains running to both Morden and
Camberwell.

Now that is something I'd not heard before! Do you have any more
information?

I can't find where I read it; sorry. It's not in the two or three
obvious places I tried first.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is: