On the subject of Presidential portraits on U.S. coins, NBS Vice President Tom Sheehan correctly notes:

Former NBS Board member Pete Smith writes:

David Lange adds some more details:

If Ken Lowe were here, he'd be making some crack about The Lone Ranger, but yours truly was moved to consult a dictionary. The online Merriam-Webster dictionary (http://www.m-w.com/) lists this definition for tondo: "Etymology: Italian, from tondo round, short for rotondo, from Latin rotundus Date: 1890 1 : a circular painting 2 : a sculptured medallion "

Michael Schmidt also noted the medallic source for the right- facing Lincoln portrait. He went on to note that

Dick Johnson discusses another dimension of portrait direction:

Like my Mom always says, "You learn something new every day." E-Sylum subscribers are a living numismatic encyclopedia. Thanks to everyone for your interesting responses.