Another evening, another function, this one sponsored by the More Maths Grads programme. Dr Reidun Twarock, to whom I spoke earlier in the day, gave her talk on viruses and symmetry, possibly the most interactive maths I have seen. Icosahedrons made from cardboard and real footballs were thrown into the audience to help explain her mathematical concepts, and the talk was followed by a brief function in which the More Maths Grads people promoted their activities.

Journeying in this morning, I regretted somewhat the dodgy Yorkshire fish and chips I had the night before. I attended a press conference on studies conducted by the University of Bristol that suggests that not only is there trace evidence of drug usage on nearly every UK bank note in circulation, but that the notes circulate quickly enough throughout the country that no particular area has higher instances of drug use on their notes. Cocaine was found on nearly every note, whilst heroine is found on around 5%. The presence of the drugs is not simply because notes are used in drug-taking activities - even fresh new notes have some contamination because they are contaminated very early on through contact with infected notes. Cocaine is particularly sticky, and so only very brief contact can contaminate a note.

The next press conference was from Professor Terence Cosgrove from Revolymer, who has developed a non-stick chewing gum. More to the point, he was at pains to note that it is not "non-stick" but rather "low-adhesive". He has made the chewing low-adhesive by introducing a patented polymer that has hydrophilic ends, and so will wash off the pavement with water.

I spent the afternoon chatting to Plus editorial board member Chris Budd about all sorts of mathematical issues - mainly that of Euler and the role of maths in the food and drink industry. But we also touched on mathematics communication, period costumes, maths in crime solving and maths in Celtic and African knots and art. You can hear all this on the podcast very shortly.

Unfortunately my time at the BA Festival of Science is coming to an end. I am about to head into York for a session entitled "How maths changed my life" followed by the last train back to London. I certainly look forward to attending the 2008 version in Liverpool.