COULD it be true that Scienceworks just happened to pick Luna Park's centenary year to dream up an exhibition exploring the science behind carnivals, sideshows and circuses? Is it mere serendipity that Carnival of Science opens on December 15, two days after the 100-year anniversary of Mr Moon opening his giant mouth for the first time? Are these ''coincidences'' somehow the work of Zoltar, a fortune-telling machine common to sideshows?
Carnival of Science brings together more than 30 interactive versions of classic carnival attractions - from Zoltar and the mirror maze to Pepper's Ghost, an optical illusion that makes objects or people appear to transform wildly - and reveals the physics, mathematics and psychology that make them work.
Exhibition manager Andrew Lewis says the fortuitous timing of Carnival of Science owes less to Zoltar than to Questacon, Canberra's national science and technology centre. Colleagues from Questacon called Lewis late last year to offer Scienceworks its long-running exhibition Sideshow, which was being dismantled.
''The amount of work that goes into these [exhibitions] is extraordinary,'' Lewis says. ''And it's always tragic that after they've had what's deemed an effective lifetime it's all thrown in the bin. The colour and vibrancy of this stuff was just a natural fit for Scienceworks. The physics messages are wonderful, too.
''Physics is a difficult thing to communicate and when you construe it into a … fun, carnival-type environment, it makes it far more palatable.''
Lewis cheerfully admits to failing maths and science at school, but has clearly learnt a thing or two about both in the decades since. He has combined 19 hand-picked exhibits from Questacon with 17 interactive designs of his own, which have been built in Melbourne. His inspiration came not just from sideshow concessions popular around the world, but also playground equipment and vintage toys.
Each exhibit conveys complex scientific principles with a minimum of words and a focus on interactivity and learning-by-doing known in the industry as ''bodying''. A mini human cannonball, for example, requires kids to figure out through trial and error the exact force and elevation needed to hit a target. Ride-on spinning tops demonstrate centrifugal force. A guillotine called Face Your Fear explores the psychology of dread.
Not for the faint-hearted, the bed of nails delivers 3600 sharp little reminders of Pascal's law and the mathematical principle that pressure is equal to force divided by area. Its manufacturer, design engineer Paul Ket, says Lewis' bed of nails is ''designed to show that … if the area of the nail points add up to a reasonable area, then the specific pressure on any part of your body is so light that it's not a problem, it doesn't hurt you''.
Ket is a regular collaborator with Lewis (he created several exhibits for Carnival of Science, as well as Scienceworks stalwarts such as the Nitty Gritty Super City). He's also the man behind TV's lotto machines and a host of interactive displays for the Australian Centre for the Moving Image at Federation Square; Healesville Sanctuary; and Melbourne Zoo. He says that for an object often associated with mystics, the bed of nails is straightforward. ''Andrew wanted us to have a table which users could climb onto, lie down, and just by simply pulling an air valve … raise the bed of nails underneath them and be lifted off the table,'' he says. ''[The brief] was simply to have nails … at a sufficiently close pitch so that you still felt the points of the nails but there was no danger … to the visitors.''
There's also a quick-release mechanism ''so that if anyone does panic when the nails come up, albeit slowly, they're able to just take their hand off the control and it will automatically drop down again''.
For Lewis, revealing the scientific theories underlying carnival and fun park attractions has proved enormously enjoyable. Did he ever worry that in the process he would shatter illusions and end up spoiling the fun? ''An exhibition on magic would be very difficult,'' he concedes.
''Usually these things have very good explanations, but if you go and explain it it totally ruins it. That didn't really concern me here. Pepper's Ghost, I think, is probably so ho-hum in terms of illusion, but still relevant inasmuch as it's a great effect.''
■ Carnival of Science opens on December 15. Details: museumvictoria .com.au/scienceworks