This week is all about the history of salt! Yes, salt. You've probably never given it much thought. It sits in a salt shaker on your kitchen counter, spice rack, or cabinet. You can buy a pound of it for 76 cents at Walmart right now. But, believe it or not, salt was once an extremely valuable commodity. Whole civilizations rose up over salt. Trade routes were established. People became very wealthy. Salt allowed for the preservation of food which allowed humans to travel over long distances....