You grab your hat and mime that it is floating.
The Frenchmans eyes light up with a look of fear, envy and loathing.
Your hat floats and you mime fighting it back onto your head, you let it drift up and float up to the Frenchman, he grabs it and it appears to lift him up out of his saddle. His feet slip from his stirrups and it looks as if he is about to get off the horse.
Alas, he then plucks the feather from the hat. It then becomes heavy as lead and he drops it down back onto you head and he settles back into his saddle.
Do you:-
Mime a lasso and attempt to pull him from the horse
Shout louder and slower ‘Get off the horse’