The penny bank craze of the twentieth century began quietly enough. Here, a slotted pottery pig from Scotland. There, a grimacing human face made in Bennington, Vermont. In 1793, penny banks first appeared in America, along with the first large copper pennies. Those who mistrusted paper currency saved their "hard" money in vessels of pottery, glass, and tin. In the 1890s, "China Pig" with a slit in his back sold for a dime. Plump pigs and pennies...