Roland Perry wrote:
In message -septembe
r.org, at 10:02:29 on Sun, 24 May 2015, Recliner remarked:
Tuffers was one of those stations that had a rather annoying lift/
escalator characteristic. At the top landing the lift goes almost to
street level. There is a further flight of about 10 steps. At the
lower level the lift goes almost to platform level - there is a flight
of about 20 steps. Lots of other stations have this charming
idiosyncracy. It's a major design flaw.

The former is usually because there needs to be a mini concourse which
has access to both platforms, and it can't be any lower because the
tracks are in the way. I'll speculate that the latter is so that the
lift's machinery room can be at ground level.

They managed it at Caledonian Road.

No constraint to be under roads there, though. The Piccadilly runs under the
much wider GN Main Line.

While the Piccadilly Line is constrained to being under roads through
most of Central London it breaks away just south of Russell Square and
all the way to Kings Cross. The line is in fact a merger of routes: from
Finsbury Park to Holborn and Hammersmith to Piccadilly, joined with a
third stretch from Piccadilly Circus to Holborn.

That was the legal basis, but were the tunnels themselves constructed as
though for three railways that had already been combined before
construction started?

It think it was constructed as one line, but maybe the two main sections
had previously gained Parliamentary approval with different rules about
being constrained to "under roads" or not.

Was the constraint about lines not running under buildings a legal
limitation, or a prudent decision by the tunnellers to minimise the chances
of being subsequently sued by building owners over cracks that developed
once the trains were running?

In message
-septem
ber.org, at 10:28:37 on Sun, 24 May 2015, Recliner
remarked:
While the Piccadilly Line is constrained to being under roads through
most of Central London it breaks away just south of Russell Square and
all the way to Kings Cross. The line is in fact a merger of routes: from
Finsbury Park to Holborn and Hammersmith to Piccadilly, joined with a
third stretch from Piccadilly Circus to Holborn.

That was the legal basis, but were the tunnels themselves constructed as
though for three railways that had already been combined before
construction started?

It think it was constructed as one line, but maybe the two main sections
had previously gained Parliamentary approval with different rules about
being constrained to "under roads" or not.

Was the constraint about lines not running under buildings a legal
limitation, or a prudent decision by the tunnellers to minimise the chances
of being subsequently sued by building owners over cracks that developed
once the trains were running?

Whichever one dominated the decision, it clearly made differently for
the two halves.
--
Roland Perry