automatic windscreen clearer

The designer of this circuit must have had frequent occasion to become annoyed at the various pamphlets, posters and advertising `bumph` which is left under the windscreen wipers of parked cars, for he has come up with a radical antidote -an automatic windscreen clearer. Unfortunately this ingenious device has one slight drawback, any meter-maid or passing policeman who tries to leave a parking ticket under the wipers might well be less than pleased to see the ticket being repeatedly pushed off the windscreen (although perhaps some of our readers will find this prospect an added attraction).