'Magic' show delights budding chemists

The land of O₂ (yes, as in oxygen), was wilting. Pollution from the greedy witch's factories was destroying forests, dirtying the air and generally putting a damper on things.

Huffing and puffing: The Wizard of O2 (centre) helps two young audience members re-inflate a balloon by breathing on it.	Do not drink: (from left) Dorothy, Scarecrow and Toto the dog discover how to test whether water is clean or dangerous acid rain.

Young Dorothy and her dog, Toto, set out in search of the Wizard of the Emerald City in the hope that he would defeat the witch and save the dying land.

Their journey - brought to life by postgraduate students in UCT's Department of Chemistry for hundreds of schoolchildren in the annual Christmas Jack Elsworth Lecture on 29 November - was, of course, based on L Frank Baum's The Wonderful Wizard of Oz. The children laughed and gasped as the travellers joined forces with a scarecrow, sad because the crops she was meant to protect were dying thanks to acid rain; a rusting Tin Man (thanks again, acid rain), and a cowardly lion, all of whom were determined to seek out the Wizard, played by Professor Allen Rodgers.

Along the way, the travellers sneaked in a number of scientific lessons and chemical experiments, from using an indicator to distinguish between clean water and destructive acid rain, through designing a variety of methods to light their path out of the Dark Forest. The young audience found this a hoot; as one chirped during the show: "I like the experiments every time!"

The Wizard - who 'fried' eggs for the weary party when they arrived at his door using freezing liquid nitrogen ("It's the opposite of burning," ventured the same enthusiastic youngster) - marshalled Dorothy and co in an epic battle against the witch and her forces, complete with ear-popping explosions caused by flames meeting unfortunate helium balloons.

Needless to say, the profit-hungry witch was defeated and reduced to nothing more than a pile of sticky green stuff, which the children stuffed into their pockets as a gooey memento.

The Royal Society of Chemistry, whose local chapter organise the Jack Elsworth lecture in honour of the late UCT academic of that name and that held similar fun chemistry lessons for schoolchildren, could be pleased that a new generation of chemists were suitably enthralled by the 'magic' of science.