On Wed, 25 Mar 2009 09:41:30 UTC, "Roger Mills"
wrote:

In an earlier contribution to this discussion,
John wrote:

"Arfa Daily" wrote in message
...


I thought that the ones that I had seen, had the grooves in the
moving walkway, slightly off-parallel, so that when the wheel edges
dropped down into them, they 'locked' in place, as gravity tried to
drag them deeper into the diminishing gap ?

Arfa


The ones I have seen also have a claw / sawtooth type feature.

Slightly OT, but at (I think) Zurich Airport they have got luggage trolleys
which can go up and down proper (step-type) escalators - and remain upright!

Nearer home...Victoria Station!
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