Andrew explores the well know but perhaps not so well understood Archimedes principle. We start off in ancient Sicily for a surprising dip in the bath with Archimedes, followed by a variety of experiments and demonstrations back in Andrew's basement lab. the properties of both liquids and gases are explored in a whistle-stop tour of this ancient but still vitally important scientific principle. Chapters: 00:00 - Archimedes and the golden crown 07:45 - Introduction to Archimedes principle 08:30 - Using Archimedes principle experimentally 16:07 - Rubber, and Hooke's Law 19:23 - The hydro-static balance 20:45 - Liquids, gasses and compressability 24:51 - Archimedes principle with elastic fluids 28:59 - Compressible hydrogen gas 30:42 - Buoyancy 34:36 - Summary Andrew Szydlo is a chemist and secondary school teacher at Highgate School, well-loved by pupils and Ri attendees alike. He has given public lectures around the country, been featured on TV shows and has become a popular regular face on our channel. Subscribe for regular science videos: http://bit.ly/RiSubscRibe The Ri is on Patreon: https://www.patreon.com/TheRoyalInstitution and 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