Dickens called her "that little darling", Thackerey thought her "easy to fall in love with". President James Buchanan was "an immense friend", and Henry Adams modeled the heroine of a best-selling novel after her. She danced with Prince Albert and traveled Italy with General George McClellan. A nineteenth century female Zelig, she managed to be in all the right places with all the right people. As the wife and widow of diplomat T. Bigelow Lawrence...