On Tue, 8 May 2007, Clive D. W. Feather wrote:

In article .com, alex_t
writes

Well west.

So it will go to: Euston - west of MC - Camden Town - ... -
Edgware?

At Euston the two branches of the Northern Line are approximately at
right angles. The CX branch runs along Eversholt Street,

Whereabouts does it head over to Tottenham Court Road, if i may ask?

while the Bank branch takes a large loop, converging with the CX branch
just south of Camden Town. There are then the complex junctions, after
which the two branches follow along the two main roads northwards.

idle-speculation

I was wondering, as i was sat on it this morning, whether it would be
possible to construct a connector between the Bank and CX branches around
about Euston, so that they could act as two arms of a loop, with trains
running Kennington - Bank - Euston - Charing Cross - Kennington and vice
versa. Based on what you say, perhaps not.

If so, though, it could be a useful way of focusing trains on the
termini-to-town section of the line, which i assume is the most heavily
loaded, either for extra trains during the peaks (which wouldn't need to
negotiate the delay-inducing Camden Town chicanery) or off-peak (when
demand to the suburbs is less). I don't know where you'd put the
platforms, how much worse the extra set of junctions would make the line's
reliability, or how confusing it would be for passengers.

Looking at tis map of Euston on John's site:

http://www.geocities.com/Athens/Acro...9/lteuston.gif

.... it seems that it might be plausible. For the clockwise route, drive a
tunnel from the northbound Charing Cross branch some way south of the
platform, drop down to the level between the two branches, run along under
the branch, then dive to join the southbound Bank branch just 'north' of
the platform, perhaps exploiting the old northbound alignment. For the
anticlockwise route, start your tunnel from the northbound Bank branch at
what remains of the northbound alignment, and is now a reversing siding,
to the 'south' of the platforms; climb over the southbound Bank platform,
turn north, and loop round to join the southbound Charing Cross branch
just north of its platform. Provided there's as much vertical separation
between the branches as i hope there is, and provided there's nothing
awkward underground to the north of the Bank branch platforms (er, Euston
station itself?), this would avoid some of the major complaints - all
trains to Bank and Charing Cross would go from the same platform (IYSWIM),
and there would be enough track in 'limbo' between the main routes of the
branches to hold a train or two, so helping avoid head-of-line blocking -
rendering this idea merely bad, rather than terrible.

/idle-speculation

Hmm. That map implies that the northbound City track passes *under* the
Victoria line, whereas this cut-away drawing:

http://www.geocities.com/Athens/Acro...9/lteusmod.jpg

Shows it passing *over* it. Anyone know which is right?

tom

--
The fundamental cause of trouble in the world today is that the stupid
are cocksure while the intelligent are full of doubt. -- Bertrand Russell