Tom Anderson wrote:
On Thu, 26 Apr 2007, Dustbin wrote:

You cannot build tunnels across continental plates.

A Bering Strait bridge is the answer; one platter can rest upon
rollers with each end on different continents. It would still
require good maintenance and the platter would have to be replaced
regularly but it is not impossible.

How do you interface the track running across it at the ends, though?

http://commons.wikimedia.org/wiki/Im...b_ExpJoint.jpg

Or... the track leaves the platter sideways. When the platter moves, the
track moves sideways (similar to points) but doesn't have to change length.

On Fri, 27 Apr 2007, John Rowland wrote:

Tom Anderson wrote:
On Thu, 26 Apr 2007, Dustbin wrote:

You cannot build tunnels across continental plates.

A Bering Strait bridge is the answer; one platter can rest upon
rollers with each end on different continents. It would still
require good maintenance and the platter would have to be replaced
regularly but it is not impossible.

How do you interface the track running across it at the ends, though?

http://commons.wikimedia.org/wiki/Im...b_ExpJoint.jpg

Or... the track leaves the platter sideways. When the platter moves, the
track moves sideways (similar to points) but doesn't have to change
length.

The track on the platter would have to be a segment of a circle, with the
exit track being a radius, of course.

Alternatively, how about something like a set of points, with the exit
track branching off the platter track, where the platter rails can slide
through the whole assembly. You couldn't have the notch in the main track
rail you usually have at points; perhaps you could grade the branch rails
a bit, and have them fly over the main rails. Does that make any sense? I
should draw a diagram ...

tom

--
YOU HAVE NO CHANCE TO ARRIVE MAKE ALTERNATIVE TRAVEL ARRANGEMENTS. --
Robin May

Mike Harvey:
There was a marvellous 1972 SF novel called "A Transatlantic Tunnel
Hurrah!" by Harry Harrison, (an Anglophile American) in which he
depicts a kind of parallel-universe situation

("Alternate history" is the usual term.)

where the British Empire
still exists and contains the American colonies. ...

It was called "Tunnel through The Deeps" in the USA.

I liked that the trains were nuclear-powered.

An earlier novel of a transatlantic tunnel was "Der Tunnel" by Bernhard
Kellermann, filmed under the same title in 1933, then remade in English
in 1935 as "The Tunnel" (British title) or "Transatlantic Tunnel" (US
title). I've seen this. I was amused to see that they have the tunnel
breaking into a volcanic zone halfway across the Atlantic, which was
unknown at the time!

I was also amused in that the excavation of the tunnel apparently produces
*no* spoil...
--
Mark Brader "How diabolically clever: a straightforward message!
Toronto Only a genius could have thought of that."
-- Maxwell Smart (Agent 86)

My text in this article is in the public domain.

On Thu, Apr 26, 2007 at 05:09:28AM +0000, Dustbin wrote:

You cannot build tunnels across continental plates.

I take it you are aware that Britain and France are moving relative to
each other?

--
David Cantrell | Official London Perl Mongers Bad Influence

I caught myself pulling grey hairs out of my beard.
I'm definitely not going grey, but I am going vain.