An educational short produced in 1966 featuring an actor dressed sort of like Felix Adler narrates some footage of the Cole Bros. circus setting up the tents. The film then abruptly changes to the midway of the Clyde Beatty Circus (this is not the "Clyde Beatty-Cole Bros. Circus, which toured from the late 50s through 2001 or so) and sometimes back again as the performance starts.
It's an interesting look at the old tent show days, with three rings presented under the big top, rain or shine.
It's made more interesting for us by the fact that at about 14:00 you'll see a group of clowns outside the tent. Look carefully and you'll find Bobby Kay amongst them.
At about 16:15 or so you'll see Bobby riding on an elephant in opening.
At one point you'll see a tramp clown driving a float. This is not Otto Griebling and it is not Joe Jackson but he looks quite a bit like both.
And at the end you'll see just how much Emmett Kelly had effected the popular conception of what a clown does.