Knocking down a shed with an air cannon

[TrevorJ]

http://www.youtube.com/watch?v=IyAyd4WnvhU&eurl=http%3A%2F%2Fgizmodo.com%2F5326372%2Fgiant-gas%2Bpowered-vortex-cannon-destroying-shed-filmed-at-1300fps%3Fautoplay%3Dtrue&feature=player_embedded

[slackenerny]

The travelling vortex ring of gas is known in literature as the Helmholtz soliton.

Scroll over to “Five Minutes of Knot Theory History” for a short video from demonstration class: http://www.southalabama.edu/mathstat/personal_pages/silver