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.
Volcanic gases are probably the least showy part of a volcanic eruption, but they can be one of an eruption's most deadly effects. Most of the gas released in an eruption is water vapor (H 2 O), and relatively harmless, but volcanoes also produce carbon dioxide (CO 2), sulfur dioxide (SO 2), hydrogen sulfide (H 2 S), fluorine gas (F 2), hydrogen fluoride (HF), and other gases. All of these gases can be hazardous - even deadly - in the right conditions.