The speech standard of the Ming and Qing empires was called Mandarin language by European missionaries, translating the Chinese name Guanhua (the language of the officials) for this speech standard, which was current already in the Ming Dynasty.
Producer gas is made by blowing air through an incandescent fuel bed (commonly coke or coal) in a gas producer. The reaction of fuel with insufficient air for total combustion produces carbon monoxide (CO); this reaction is exothermic and self-sustaining.
Carbon monoxide is produced when fuels such as gas, oil, coal or wood do not burn fully. When a fire burns in an enclosed space, such as a room, the oxygen is gradually used up and replaced with carbon dioxide.