I wrote:
Other sources suggest that 45.01 is the correct figure for HSK buffers
and 45.03 for the midpoint of the through lines. Though that doesn't
feel quite right.

On the other hand, one source suggests that the kilometrage stops
decreasing at 45.34 and starts increasing again. I can't think why it
would, though.

I had some time in hand this morning, so I went and looked.

Firstly, Quail and my other sources that use the 45.65 figure are plain
and simply wrong. How do I know? Simple. There's a 45.0 kilometre plate
*on the station wall*.

Further observation shows that there are plates attached to various
sleepers with kilometrages marked on them. In particular:

* A plate at the south end of platform 2 is 51.015km.
* A plate at the south end of platform 3 is 45.110km.
* A plate at the south end of platform 4 is 45.094km.
* Pacing it out, platform 3 starts about 15m south of platform 2.
* The platform 3 buffers are about level with a plate stating it is 100m
north of the south end of platform 2.
* Platform 2 ends about 25m beyond that point.

If a D stock car is 20m long, these are consistent with each other:
Circle District
51.030 45.110 south end of platform 3
51.015 45.095 south end of platform 2
51.014 45.094 south end of platform 4
50.915 44.995 platform 3 buffers
50.890 44.970 north end of platform 2

This would make the nominal mid-point of the station 50.960/45.040,
which isn't too bad a match for the 50.97 in various sources.

However, the 45.0km plate is, as best I can judge, 40m south of the
"100m" plate and so 60m north of the south end of platform 2. That puts
it at 50.955/45.035. That's a *serious* discrepency. There's no sign of
the 51.0 kilometre plate that ought to be around the station somewhere.

Finally, near the north end of platform 2 is a plate saying that this
sleeper belongs to the District, the next one to the Circle, and that
the sleeper is at 50.900km Circle and 45.570km District. That's fine for
the former but not the latter - it should be 44.980. It's not measured
via Gloucester Road either - that would be 46.32 (Inner Rail) or 46.35
(Outer Rail).

It's also possible that these data plates are lying. If anyone sees any
others at nearby stations, please report the values on them.

[There are two kinds of plate. One gives the station name and distance
from the start of the station. The other gives various numbers I haven't
identified but includes, in small print at the bottom, the kilometrage,
line, and a date.]

--
Clive D.W. Feather, writing for himself | Home:
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