Common name in Austria (also steam pipe) for the ventilation shaft that leads upwards from the wine cellar into the open air for the purpose of ventilation; the end is called the roof pipe (see in the picture). The steam pipe was also used to extract the fermentation gas (carbon dioxide) produced during fermentation. The fermentation gas was also discharged via the so-called fermentation grate. However, both devices are only suitable to a limited extent because the toxic carbon dioxide is heavier than air and collects at the bottom or at the lowest point. In order to determine the degree of fermentation gas present, the extremely unsafe method of candle testing was used. Today, the carbon dioxide is extracted via exhausters (ventilators) and led into the open air or, in large cellars, also into containers and utilised. The wine cellar was a popular meeting place for friends and like-minded people, where they discussed, philosophised and politicised over a good glass of wine and also "gossiped" about other (absent) people. It is said that many an explosive conversation was overheard via the roof pipe or opening. See also other winegrowing curiosities under winegrowing customs.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)