Possible Clues:

• French panto clown with whitened face
• Would his playing cause the jetty to decay?
• Period; incantation
• Clown playing nonsense on promenade
• An entertainer putting rubbish on the jetty
• Entertainer offered support to king that's been overthrown
• An old overseas entertainer
• Clown's depression - without sin nothing
• Is what used to perform on it the reason for the decay of what goes into the sea?
• Male clown from French pantomime