Liquid Nitrogen

When I saw the clouds I thought it might be liquid oxygen. I imagined the man breathing it in and wondered whether it might upset his system. Only now, thinking about it, I wonder whether clouds of oxygen boiling off might be a fire hazard.

I asked him, and he said it was liquid nitrogen. Then I thought of nitrogen narcosis suffered by deep divers. How the mind runs off with thoughts.

He said he was delivering it to the doctors’ surgery where they used it to burn off warts, etc.

For that amount of liquid nitrogen, how many warts must there be in Cambridge?

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Photographed with my iPhone 8