Our friends over at the always excellent Notcot were recently playing around with a microscope and noticed what certainly appears to be a typo on the US visa and border crossing card. The back of the card has very tiny etchings of every US president and every state flag -- but the etching of 6th US president John Quincy Adams appears to have a typo, calling him John Quincy Adames with an "e" added into the last name. Take a look:

That seems like a pretty big mistake. However, some are suggesting that it was done on purpose. In the comments to the Notcot post, two specific theories are presented: the first is that JQA changed his last name to distinguish himself from his father. Doing some quick searches around various bios of Adams, however, shows absolutely no support for this one. Even the White House's own page on JQA spells it Adams and makes no mention of such a change.

The other explanation makes a lot more sense. It's that this is a form of fraud/counterfeiting detection. Similar to how dictionaries would sometimes insert a fake word or phone books would insert fake people/numbers to try to "catch" if anyone was copying their work, perhaps the US government added the extra "e" on the assumption that counterfeiters would actually spell JQA's name correctly -- thus giving them a way to spot a fake. Of course, that's a pretty weak form of anti-counterfeiting, but in combination with some other techniques, perhaps it's useful. Either way, it's an amusing bit of trivia...