One of the highest moments in Grateful Dead history came on September 16, 1978, in front of the Great Pyramid of Gizeh, when a rhythm and percussion choir led by Mickey Hart’s friend Hamza El Din opened for the band’s second set  by playing his song “Ollin Arageed.” As they sang and percussed, the moon went into eclipse.  One by one, the band members drifted on to the stage and joined them, eventually going into “Fire on the Mountain.”  It was pure magic.