i am absolutely certain that writers far more eloquent than I could put this much better but I just feel the urge to shout:
"OI!!! NUTTER, get down from there before you do yerself a mischief. No one likes a show off, what if you fall off and land on some poor bastard's swede? Yeah, that's right, you ain't thinking straight, get down now before I come up there and get you!