Midwife Mercada Dasa lived in the Old City of Jerusalem until 1948. In her attic she raised an unusual pet -- a white female snake about a meter and a half long -- and fed it sugar cubes. Just before the entry of the Jordanian Legion she left the besieged city with her family and her pet remained behind. That a midwife, whose family lived in Jerusalem since the time of the Second Temple, carried on a tradition of feeding white female snakes was part of the family's lore, but not something anyone considered significant. Now Mercada's grandson, Benny Avigdory,...