Speaking of "Rio Grande," Curtis and the Sons of the Pioneers also sing “My Gal is Purple” (Stan Jones, 1950) and “Aha, San Antone” (Dale Evans, 1948).

Peadar Kearney wrote "Down by the Glenside" around 1916.

I learned the word "anachronism" while studying "Julius Caesar" in seventh grade. Shakespeare refers to a striking clock, an innovation that didn't exist in 44 BC.

Historical movies are so full of verbal anachronisms that there's almost no place to start.

OK, how about this? A Civil War drama on PBS ("Mercy Street") has a nurse in 1862 offering someone a cup of tea from the colonel's "private stash."

And then there's the Civil War movie "The Hunley," which has a sailor singing "Fiddler's Green" in 1864 - allegedly an old Irish song he learned from his mom.