“Free banking systems maintained exchange-rate stability by giving people the right to convert banknotes and deposits into gold or silver at a fixed rate. Free banks issued notes denominated in the main currency of the region where they hoped the notes would circulate. There was not a proliferation of different monetary units; in fact, during free banking’s heyday in the 1800s and early 1900s there were fewer major monetary units than there are today.” Dowd, Free Banking