Blackpowder
I tend to forget that blackpowder while fizzy when outside becomes gassy and fierce when enclosed even a little bit. Anvil launching as sport - uk.youtube.com/watch?v=4k8LAut2E6Q and uk.youtube.com/watch?v=KeNP4i47oeU
(, Sat 31 Jan 2009, 21:43, Reply)