RULE 27. TRIP TO TERMINAL AND RETURN.  Engineers required to make short trips from a terminal to an outlying point and return, from an outlying point to a terminal and return, or from an intermediate point to another intermediate point and return, on account of engine failure, running for fuel or water, running for wreck car or carmen or on account of a derailment, when such conditions arise in connection with their own train, will be paid continuous time or mileage.