In 1937 he and a few of his friends used one of his parade balloons for a hoax in Nantucket. He advertised sightings of a sea serpent, and followed it with giant footprints on the beach.
By the time the giant monster appeared on South Beach, newspaper articles had built the anticipation.
Nearly everyone in Nantucket came down with their cameras to see the beast, and as a result many photos survive.
-----Here's a Flickr collection
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