After lunch I spent a few minutes looking at the exhibits in the Borax Museum -- housed in the oldest building in Death Valley.

I enjoyed learning that Twenty-Mule Teams were normally made up of 18 mules and 2 horses.  The mules were arranged with the smartest two in the front of the train, with the next two smartest following -- all the way to the dumbest two who were stationed right in front of the two horses that immediately preceded the wagons.  I don't know how they determined which mules were "smart" and which were "dumb."