Americans have a new way to celebrate the Fourth of July: Drop Mentos candies into 2-liter bottles of Diet Coke and watch as the soda shoots skyward. For the messy technique, thank Fritz Grobe and Stephen Voltz.

Stephen Voltz, left, and Fritz Grobe, both of Buckfield, Maine, create a geyser effect from a combination of diet soda and Mentos mints, Thursday, June 29, 2006, during a taping of 'Late Show with David Letterman', in New York. [AP Photo]

The two performers from Buckfield appeared in a three-minute Internet video in which they don goggles and lab coats and show the world how to create the geysers. The resulting 20-foot blasts have captured the imagination of millions.

"We told friends we thought it would take a few weeks to catch on," Grobe said. "Literally, within hours we were seeing thousands of hits."

The two began experimenting eight weeks ago after Voltz learned that cola plus candy equals a frothy mess. It's an old trick, but the pair took it to new extremes.

Grobe, a juggler, and Voltz, a trial lawyer, enlisted Mike Miclon, the owner of the theater where they perform, to operate the camera and a friend to create the toe-tapping techno music soundtrack. Miclon said his wife held an umbrella next to the camera just in case.

The result is their video, which features 523 Mentos causing 101 bottles of Diet Coke to erupt.

The geysers have been compared to the dancing fountain at Las Vegas' Bellagio hotel-casino.

Any kind of soft drink will work, Grobe said, but diet soda keeps the men from getting sticky.

The video has had 4 million hits on the Web since it was posted on June 3 and exposure in the mainstream media, including David Letterman's "Late Show" on CBS and NBC's "Today" show.

Coke and Mentos have embraced the phenomenon. Mentos, a subsidiary of Perfetti Van Melle USA, Inc., features the video on its Web site, and a Coca-Cola Co. spokeswoman said the Atlanta company is pleased that people are having fun with it.

"You never can tell what's going to capture people's imagination," said Susan McDermott, the spokeswoman. For the record, she noted, people won't suffer harm from chomping Mentos and washing it down with Diet Coke.

Grobe said he and Voltz see a bright future in being madcap scientists.

"The next crazy project is bigger and better and will pack a lot of surprise," Grobe said. "You can look forward to something pretty amazing."