On 6 November 2008, SCI's Cambridge and Great Eastern Regional Group held a spectacular lecture titled 'Fireworks and waterworks'. The speaker, Dr Andy Szydlo, has over 35 years experience giving chemistry demonstrations, and has appeared on both the UK's Channel 4 and the BBC in recent years.
Dr Szydlo exceeded all expectations; he raced through vast tracts of practical chemistry, history, alchemy, the discovery of oxygen, the internal combustion engine, and on occasion, introduced music too. His lecture was interspersed with flashes, bangs, colour changes, detonations and eruptions, keeping the 350-strong crowd on the edge of their seats throughout. Dr Szydlo mixed a crude gunpowder from its three constituents, then demonstrated the superior ignition of industrially prepared black powder. Using this, a sheet of A4 paper and a roll of tape, he made and exploded a very effective banger.
To enliven a demonstration of the iodine clock reaction, where each of four beakers of colourless liquid in sequence suddenly turned dark blue over two to three minutes, he and a helper, played a violin duet, timed to end as the final solution darkened. Towards the end of the lecture, he demonstrated a cardboard tube ‘cannon’, mounted vertically on the lecturer’s demonstration bench. The projectile was a tennis ball, placed on a couple of pieces of gun cotton. The audience watched with anticipation as he lit the fuse. There was an orange flash and a bang, and the tennis ball seemed to disappear. When the smoke cleared it became apparent to the bemused audience that the tennis ball had exited through the false ceiling, punching a small hole! (Dr Szydlo had not realized that the ceiling was not solid.)
The lecture was a tour de force, although it may yet mark the end of a long and happy relationship between SCI and the Cambridge Department of Chemistry when they find a hole in the ceiling of their lecture theatre! The lecture was closed with the ‘Last Post’ on the bugle to accompany the mixed pyrotechnic finale.
John Wilkins
Chairman of SCI’s Cambridge and Great Eastern Regional Group
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