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November 1861: Chalmers' under Channel railway

(www.theengineer.co.uk)
22 points timthorn | 1 comments | 18 Nov 24 14:52 UTC | HN request time: 0.21s | source
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WalterBright ◴[18 Nov 24 17:02 UTC] No.42174361[source]▶
Not mentioned is what to do with the smoke from the locomotive. I expect all the passengers would asphyxiate before they emerged from the other end.
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noneeeed ◴[18 Nov 24 17:22 UTC] No.42174583[source]▶
They have another article about a more conventional tunnel idea that addresses that issue. They were well aware of the issue. The only way to make this work at that time would have been something like Brunel's atmospheric railway. That was plagued by issues when in the open, goodness knows what it would have been like to run underground for such a long distance.

https://www.theengineer.co.uk/content/in-depth/this-week-in-...

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1. Animats ◴[18 Nov 24 21:14 UTC] No.42177119[source]▶
The big problem with atmospheric railways was sealing the slot in the tube where the piston inside the tube connects to the load. Early atmospheric railways used oiled leather, beeswax, and tallow. Those were not really good enough materials for the job.

There are solutions for this today. They're widely used in rodless pneumatic cylinders.[1] The seal is flexible metal strip to metal, forced closed by the interior pressure of the cylinder. In the 1980s, there was a brief revival of the technology by Aeromovel, which built a few theme park and airport systems. None seem to be still running.

[1] https://tameson.com/pages/rodless-cylinder