In the world of the circus there is no greater honor than being such a stellar performer, so popular with the crowds, as to warrant being immortalized on your very own poster. And the posters were beautiful in those days, lithographed in gorgeous colors, ranging from the standard one-sheet that is still used in the movie business today, all the way up to posters the size of a house. Your name in lights is nice, but having your own poster blazoned on the side of a building is toppermost of the poppermost.
And so we see the equestrienne May Wirth, who was just such a star, posed on the back of her white horse, whose name was Joe, in front of the Ringling Bros. & Barnum & Bailey poster that featured them.
Among other spectacular feats, Miss Wirth could do a full handstand on Joe's back, while he was galloping 'round the ring. Not for nothing was she billed on the poster (although you can't see it behind Joe) as "The Greatest Bareback Rider of All Time." The six of wands informs you of Great Accomplishments, and Miss Wirth sets the standard high.