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This was finished a few days ago. Used my newly-bought Uni-ball Signo DX UM-151 Gel Ink Pen to ink it. I absolutely love it. It's so much nicer than what I was using before.

Wikipedia on the History of Laughing Gas:
Laughing gas was first synthesized by English chemist and natural philosopher Joseph Priestley in 1775, who called it "phlogisticated nitrous air". Priestley describes the preparation of "nitrous air diminished" by heating iron filings dampened with nitric acid in Experiments and Observations on Different Kinds of Air (1775). Priestley was delighted with his discovery: "I have now discovered an air five or six times as good as common air... nothing I ever did has surprised me more, or is more satisfactory."

Joseph Priestley also discovered oxygen (really).