Now,
when you press the start button Duke should start tossing beans around in a
circle over his head like a professional juggler.
You
can control Duke's juggling speed by manually setting the property value labeled
animationRate in the Juggler's property sheet editor. For the appropriate
property sheet editor to appear, the Juggler must be the currently selected Bean
within the BeanBox frame.

To
complete the example program, add a stop button. Repeat the steps you took when
you added the start button and connected it to the appropriate Juggler action.

When
the new button is the currently selected Bean, the appropriate property editor
appears.
You should now be able to start and stop the juggler by pressing the appropriate button.