In article , John Rowland
writes
Since there would only be one train on each open section, and each open
section would be separated by several miles from the next open section on
the same track, signals wouldn't be needed. So long as the last section at
the end of the line operated on the correct line towards the terminus (and
wrong line away from it), and the tripcocks were operating here, and each
train had a driver in each end, I don't see many safety problems.

Actually you'd have a problem with the tripcocks. A train can be
"back-tripped" if the rear car passes over a raised trainstop. On bits
of track where trains move both ways the trainstops have to be lowered
as a train approaches and raised once it's passed. Plain track is
signalled like this.

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