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Flying terminus was Connectivity
Mark Brader:
As a further safety aid, the tracks at the right were actually gauntleted (interlaced), with two pairs of rails that diverged (if my interpretation is right) at the positions o. That is, in terms of individual rails, the layout at each o was: ------------------------------------------------- /--------------------------------- / -------------+----------------------------------- / /----------------------------- / / / / And if a particular train started from the south face of the departure platform, then it would use the south face of the departure platform all day, and also the south face of the arrival platform, staying always on the south rail of each pair. Tom Anderson: So each track was in fact four rails, of which only two were in use at once? There are two logical tracks sharing the same space? Uh-huh. This is more commonly done in locations where clearance considerations force what would otherwise be a short section of single track on a double-track line. Here's an old image from Colwyn Bay in Wales: http://dewi.ca/trains/lcber/b039.jpg. Another use is to allow wide trains to pass a platform on a track designed for narrow trains on what would otherwise be a single track, like this one: http://image03.webshots.com/3/0/83/44/21408344mgAUFPpzaa_ph.jpg near Chicago. The corresponding rails can also be set much closer, as on this narrow Amsterdam street. You might think this was a single track at first glance: http://www.railfaneurope.net/pix/nl/trams/Amsterdam/Combino/line_1/amsterdam_2001.jpg One more source of danger elimnated. How so? No possibility of the points being set wrong, routing the train into the wrong arrival platform, which most likely would already be occupied. (Similarly, in situations like the Welsh and Dutch examples, no possibility of the car going onto the wrong track and colliding head-on with another.) No possibility of points changing under the train, either. Is there some sort of encyclopedia of railway engineering that i could get hold of which would save you from these questions? Hey, what fun would that be? :-) -- Mark Brader, Toronto | "Any story that needs a critic to explain it, | needs rewriting." -- Larry Niven My text in this article is in the public domain. |