Dot left Murphy, NC in the car with the dogs on the day before my class began, so I batched it for a week.  On Saturday, May 11, I left before 7 am with the plan to make as much of the 600 mile trip on Saturday and finish it up on Sunday.  Approximately five hours into the drive, the left rear trailer tire exploded.  I waited for Road Service to replace it with the spare.  An hour later, the replacement exploded with equal vengeance.  After paying a significant price this time for Road Service to bring out a tire and mount it, I limped the rest of the way home, driving the Washington DC Beltway in the dark in the pouring rain at 40 miles an hour.  Needless to say, I arrived home, exhausted, near midnight.