European Railroad Discussion > Our loading gauge stinks

One of these isn't real :-)

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And ironically I'm pretty sure it's the second one.

The first one is Box Tunnel, correct?  Am I remembering correctly that the portal is far taller than the tunnel, and it funnels down just inside the portal mouth?  I know it was originally designed for two broad gauge GWR mainlines, but I don't recall Brunel building for a particularly tall loading gauge, just wide.

 

NDHolmes Wrote:
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> The first one is Box Tunnel, correct?  Am I
> remembering correctly that the portal is far
> taller than the tunnel, and it funnels down just
> inside the portal mouth?  I know it was
> originally designed for two broad gauge GWR
> mainlines, but I don't recall Brunel building for
> a particularly tall loading gauge, just wide.

You're absolutely right, the entrances to Box are simply decorative, the single bore on the down line at Dinmore is much more representative. Just west of Box is the much shorter Middle Hill tunnel with the same large portal but it's short enough to see through and you can see how much lower the tunnel is than the portals.

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> west of Box is the much shorter Middle Hill tunnel
> with the same large portal but it's short enough
> to see through and you can see how much lower the
> tunnel is than the portals.

Was this to allow the smoke from steam locomotives to escape more easily?

No, because the portals of both Middle Hill and Box are visible from the main London to Bath and Bristol road it's purely decorative.

There's also an element of celebration too, when completed in 1841 Box was the longest railway tunnel in the world, it had taken almost three years to build, had cost a fortune both in £££ and lives and was the missing link in the GWR between London and Bristol.



Edited 1 time(s). Last edit at 01/21/21 23:34 by 86235.

And yet the tracks in Box Tunnel had to be lowered for electrification.  Was this due to the European-wide standards [ which were based on DB's, I think ] vs the [ later version ] LMR's, which became BR's ?

SZ

ORNHOO Wrote:
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> > west of Box is the much shorter Middle Hill
> tunnel
> > with the same large portal but it's short
> enough
> > to see through and you can see how much lower
> the
> > tunnel is than the portals.
>
> Was this to allow the smoke from steam locomotives
> to escape more easily?

Just for show really.

Though the sun is reputed to shine the whole way through the tunnel on Brunel's birthday!

Maybe that had something else to do with it?

Posted from Android

Steinzeit2 Wrote:
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> And yet the tracks in Box Tunnel had to be lowered
> for electrification.  Was this due to the
> European-wide standards [ which were based on
> DB's, I think ] vs the [ later version ] LMR's,
> which became BR's ?
>
> SZ

And of course it's not been electrified.

Hexagon789 Wrote:
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> Though the sun is reputed to shine the whole way
> through the tunnel on Brunel's birthday!
>
> Maybe that had something else to do with it?
>
> Posted from Android

From what I've read I don't think the sun shines right the way through the tunnel ever but it's true that the rising sun does shine into the east portal close to Brunel's birthday, but closer to his sister's than his, and it differs slightly depending on the year.



Edited 2 time(s). Last edit at 01/22/21 11:24 by 86235.

Regardless of the issues, I definitely like the Class 66 photos.
ALLEN

Something about a tapered, plug-shaped tunnel just captures the imagination. I’m picturing a North American style double stack train entering the tunnel and getting squeezed and abraded, emerging on the other side as a perfect clearance diagram.

(Yes, I know it would take a really weird misrouting to get a double stack train there. and you’d probably pluck some bricks). 

86235 Wrote:
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> Steinzeit2 Wrote:
> --------------------------------------------------
> -----
> > And yet the tracks in Box Tunnel had to be
> lowered
> > for electrification.  Was this due to the
> > European-wide standards [ which were based on
> > DB's, I think ] vs the [ later version ] LMR's,
> > which became BR's ?
> >
> > SZ
>
> And of course it's not been electrified.
>
> Hexagon789 Wrote:
> ------------------------------------------
> > Though the sun is reputed to shine the whole
> way
> > through the tunnel on Brunel's birthday!
> >
> > Maybe that had something else to do with it?
> >
> > Posted from Android
>
> From what I've read I don't think the sun shines
> right the way through the tunnel ever but it's
> true that the rising sun does shine into the east
> portal close to Brunel's birthday, but closer to
> his sister's than his, and it differs slightly
> depending on the year.


Yes, apparently they didn't account for atmospheric refraction or leap years, so it is a few days off. When they were electrifying the tunnel they did an experiment and found the sun did shine right through the tunnel but on the 6th instead of the 9th. So the original tale could be true allowing for the errors.

march_hare Wrote:
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> I’m picturing a North
> American style double stack train entering the
> tunnel and getting squeezed and abraded, emerging
> on the other side as a perfect clearance diagram.

BN tried that. It didn't work out. https://www.trainorders.com/discussion/read.php?18,4204484,4204484#msg-4204484

TAW