Opening Saturday at The San Francisco Legion of Honor, "Cartier and America" features some of the most striking examples of Cartier's 'Mystery Clock,' innovative pieces valued by collectors. In 1913 industrialist J.P. Morgan became the first American to buy one. Also on view, lavish jewels, from 1900 to 2007, that show the history of Cartier is as much about dazzling design as it is about social history...