Slide, glide, twirl! Splish, splash, floop!

Rare is the children's book that begs to be read and tossed aside for a good romp — all at the same time. Rarer still are moving pictures built right in that double-dare kids to do just that.

Meet Rufus Butler Seder — equal parts artist, mad scientist and boy magician who never grew up.

From a studio in Waltham, Mass., Seder created two hugely popular picture books with unique black-and-white images that trick the eye and come alive when pages are turned. The look is a bit like holography — only it isn't.

"It's about the magic," Seder said. "It dates to my days as a junior magician with my Remco magic kit. It's creating that illusion that fires the imagination."

To create his moving pictures, Seder uses a layer of multiple images printed on a sheet of paper under a layer of vertical lines akin to a picket fence on clear acetate. When the page is turned, the reader's brain unscrambles the images underneath and prompts the eyes to see motion.

No electricity, motors or special lighting are required. The books have no external tabs to get bent or torn since the pull is automatic as kids make their way from page to page.

Seder's latest book "Swing!" was released in September and shows children at play. He sets a young ice skater twirling and a swimmer racing across a pool. The book follows last year's "Gallop!" that includes a horse running, a butterfly fluttering and a chimp swinging from vine to vine. Action-packed text challenges kids to do the same.

"Are they trapped in there?" nearly 4-year-old Siri Waxenberg of New York City asked after getting her first look at "Gallop!" "Where are they going?" she wanted to know before dropping to the floor and paddling like a turtle.

Seder calls his patented Scanimation a lesson in "retro-tech," traceable to the mechanics of the slotted, spinning Zoetrope invented around 1850. The difference between Seder's method and other forms of animation and motion picture technology is he compacts all phases of an image sequence onto a single page, requiring less distance and speed to create the effect.

"I'm not a technology guy," he said. "I can't really add two and two. I'm a visual artist and that's how I think. There's no message. It's all about movement. I try to make it as beautiful as possible and capture the signature movement that tells you what you're looking at is real."

Seder, who spent much of his childhood in Connecticut, taught filmmaking for years while pursuing his animated art that also includes murals using clear glass tiles he kiln-fires himself to help create the appearance of movement. The books require precision hand assembly by 600 factory workers Seder helped train in China.

Interest in the books from parents and children has been swift and lasting. "Gallop!" has been high on best-seller lists for most of 2008, is available in 12 languages and is approaching 2 million copies in print. Seder's "Swing!" has already made some lists with nearly 800,000 copies in print.

"It was astonishing," Seder said. "Nobody expected it. I never get used to it. I never take it for granted."

Seder's childhood interest in animation was nurtured by his journalist-photographer father, who showed him how to make cartoons on a hand-built light table with a 16mm Bolex movie camera. He dedicates "Swing!" to: "Mom, who made things fun, and Dad, who made things work."

While he jokes about a Peter Pan complex, the 55-year-old Seder ponders how he wound up with two winning children's books.

"I like kids and they get along with me fine," said Seder, who has none of his own. "But I never felt keen on doing children's books."

So what turned him around?

"It might be something as simple as the little kid in me saying, 'Hey, look at me. Look what I can do.' It might not be anything more than that."

Seder has no plans to slow down. He'll put out "Waddle!" next year, followed by a surprise Scanimation kid book soon after that.

"I'm just darn driven by what I do," Seder said. "It's the only way I know any artist can get satisfaction out of their work. It's always better to do what you enjoy doing."