1791: John Barber receives British patent #1833 for A Method for Rising Inflammable Air for the Purposes of Producing Motion and Facilitating Metallurgical Operations.
1791年: ジョン・バーバーがイギリスで特許（第1833号、A Method for Rising Inflammable Air for the Purposes of Producing Motion and Facilitating Metallurgical Operations）を取得。