Switch puzzle

[NW Mailing List]

This image has appeared repeatedly in a switch manufacturer's ad in various railroad trade journals.  It appears to offer three different routes through it.  Can anyone explain where such a switch would be used?

Gordon Hamilton
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://six.pairlist.net/pipermail/nw-mailing-list/attachments/20130303/ef0df73e/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 41113 bytes
Desc: not available
Url : <http://six.pairlist.net/pipermail/nw-mailing-list/attachments/20130303/ef0df73e/attachment-0001.jpe>