"we're setting the ship afloat on a sea of lime green jelly," he said."

Doesn't he mean "slime green jelly?"

What color will it be after a couple of days in Bristol? (I haven't been there, and it's probably different than Philadelphia.)

Very rough estimates of the area (based on approx height of specatators for scale) suggests an initial jelly layer of about 1 inch. In a very few days the jelly will be a sheet of sticky rubber, probably less than a half inch thick, almost completely insoluble in water and - in my experience - very difficult to scrape out of the pot. I rather doubt it will be particularly easy to sweep the inevitable trash off it if it's left more than a few days, but of course all the volunteers who mixed it are commited to help with the cleanup after the event - or aren't they?

No matter. It's ART!

John