How were root beer floats invented?

Who's asking: Carolyn Bea, Alexandria, VA

It's hard to believe someone had to "invent" a root beer float, but the man who gets credit for it is Frank J. Wisner of Cripple Creek, Colorado, who dropped a scoop of vanilla ice cream into a glass of his Myers Avenue Red root beer in 1893. Locals called the drink a "Black Cow" after nearby (snow-capped) Cow Mountain.

Root beer, it turns out, is a literal name -- it's a fermented beverage made from root extracts, and the ambitious can make it at home. Although it's fermented, it's not alcoholic, for reasons I don't really understand. Fermentation is what causes the carbonation, as the interaction of yeast and sugar creates carbon dioxide and sugar alcohol. In a root beer float, the air bubbles in the ice cream act as "nucleation sites" for the carbon dioxide molecules to congregate and form giant bubbles -- which is why the root beer at the bottom of the glass is flat, after the ice cream is gone.

Root beer and sarsaparilla are essentially the same thing: carbonated beverages flavored with sassafras root and other natural flavors (including, depending on the recipe, everything from cinnamon to wintergreen). Root beer is not the same as birch beer, which is flavored with the bark of a birch tree (really). Birch beer is usually red, while root beer is usually brown.

Sassafras oil, found in roots, bark and fruit of the sassafras tree, is powerful stuff. Native Americans brewed it as a medicinal tea and used it as insect repellent. Ground sassafras leaves are a major ingredient in filé, the thickener Creole cooks use for gumbo. Concentrated sassafras oil is sometimes used in moonshine, and can have hallucinogenic properties. It's also now on the list of things that can give you cancer, so commercial root beer brewers use a synthetic sassafras flavor substitute.

Five Random Songs

"Road," Nick Drake. I whine a lot about classic music being used for TV commercials, but VW's use of "Pink Moon" for one of its ads led to a minor Nick Drake revival. That was a good thing.

"Rikki Don't Lose that Number," Steely Dan. Somewhere I read that this song was about a drug dealer, but if that's true, I don't want to know it.

"Corpus Christi Carol (for Roy)," Jeff Buckley. Tragic singer-songwriter morning on the iPod Shuffle. Jeff Buckley sings like an angel. I can only listen to this album (Grace) when I'm in a really good mood. Next...

"A Classic Arts Showcase," ...And You Will Know Us By the Trail of Dead. A friend of mine said he felt this album (Worlds Apart) wasn't loud enough, and on this song I almost know what he meant. You do need to turn it up, but the guitars sound tinny. Midway through the song it breaks and becomes something almost operatic, which I love.

"Ruined in a Day," New Order. I bought this CD (The Best of New Order) at the going-out-of-business sale of Washington's Serenade Record Store, which used to be at 1800 M Street NW. The stock was pretty well picked-over by the time I got there, but I managed to get this CD along with a Debussy collection, a good recording of Carmina Burana, and Jimmy Cliff Live in Concert. The clerk asked me, "Are all of these for you?" "Yes," I said.