I think we all learned something by the leaking tyre.
Now to go find those green stemmed tires so we can all get a good laugh when the owner comes back and finds a flat.
Nitrous oxide, also known as dinitrogen oxide or dinitrogen monoxide, is a chemical compound with chemical formula N2O. Under room conditions, it is a colourless non-inflammable gas, with a pleasant, slightly-sweet odor. It is used in surgery and dentistry for its anaesthetic and analgesic effects, where it is commonly known as laughing gas due to the euphoric effects of inhaling it.
For those who understand no explanation is needed, ...For those who don't none will.