Dr Tim Cockerill explores the science behind the most dangerous stunt in the firebreather's repertoire - the human volcano. From the volatility of the fuel to the fire breather's technique, Tim explains how the trick is performed and how everything ultimately depends on the unique properties of oxygen. Tim is a trained firebreather. Please do not try any of the stunts performed in this video at home. Find out more about Tim and his traditional acts of the fairground sideshow, including walking on broken glass and the 'human blockhead': http://www.fire‐eating.com The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter