 In this example, a train may have authority straight through from Anna through Cloy.Or, it could have authority in Anna through Bess Siding, in which case it must throw the switch between Anna and Bess and enter the siding - this will usually be done to clear the main track for an opposing train to pass.After clearing its authority in Anna siding and the opposing train passes, it might then get authority from Bess Siding through Cloy, in which case it will throw the switch between Bess and Cloy and reenter the main track.