"Children beware! It is sundown on Sycamore Street."

That's how Andrew Piccirillo started his fictitious story about two children, Bill and Terry, who walked down Sycamore Street after sunset.

"So terrible is the legend of Sycamore Street that every child in town knows never to get caught there after dark," said 26-year-old Piccirillo of Princeton, owner of Piccirillo Sciencetelling, Hillsborough, Somerset County.

At a recent presentation at the Brielle Public Library, Piccirillo demonstrated the science of gas and air pressure using water jugs, plastic eyeballs, toilet paper and dry ice, showing why Sycamore Street would be a scary place at sundown.

"Bill and Terry's story is a vehicle to present science," Piccirillo said. "So, when children learn about science in schools, they find it interesting."

Piccirillo said Bill and Terry just moved into town, and they were not aware of Sycamore Street until they toured the street late one night.

During the presentation, Piccirillo asked 6-year-old Sarah Hendricks of Brielle to pour acetone on a mannequin head made of plastic foam. Within seconds, the head appeared to turn into a one-eyed ghost, Sarah said.

"It was cool," she said.

In another demonstration, Piccirillo asked 9-year-old Rebecca Bauer of Brielle to hold a hair dryer below a plastic eyeball.

"See, this is what Bill and Terry saw," Piccirillo said. "An eye floating next to the one-eyed ghost. With the dryer we are creating a pocket of air that makes the eyeball float."

Piccirillo used a hair dryer to blow hot air onto toilet paper, creating a whirlwind.

"Fast-moving air creates low pressure that sucks the toilet paper out," he said.

Next he created white vapors from a bucket filled with dry ice.

"This is so cool," said Lizzie Takash, 9, of Brielle. "I learned that dry ice doesn't melt, it changes directly to vapors."

The evening was entertaining and informative, according to the Monmouth County children's librarian, Liz Turner, 31, of Middletown.

"He was a hit with the children," she said of Piccirillo.

According to the company's web site, www.piccirillo.org, Piccirillo Sciencetelling is a New Jersey-based organization offering interactive programs that use science experiments in telling stories.