| My original. A half-hour proof-of-concept exercise. 500 ml bottle hoiked out of a bin in someone's office. The stick came out the bin in the lab, as did the cutting of mains flex used as a hose. Three-core mains flex will fit neatly into the end of a car foot pump in place of the valve; the other end is a tight push fit for a hole in the cap of the bottle. This was set up in the end of an old bit of pipe in the car park, when all normal people had gone home, 150 ml of water and pumped until the flex blew out of the cap. Perhaps not startling, but one's first rocket is a sort of little triumph! |
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