I've previously not been aware of the Gala Ball at the Goodwood Aerodrome, this year, it was a steampunk theme

I can only find one video of it

https://www.facebook.com/494273900644168/videos/459644464549810/
https://twitter.com/search?q=goodwood+revival+ball

Last year the theme was Atlantis, and the year before that was superheroes.

http://www.lucywillshowyou.com/the-clicquot-run-stage-4-day-2-at-the-goodwood-revival-the-atlantis-gala-ball-at-the-goodwood-aerodrome/