Where does the white smoke come from?

Source: FSSPX News

From Saint Peter’s Square it was possible to discern along the edge of the roof of the Sistine Chapel the chimney from which will pour the white smoke that will indicate that the new pope has been elected.  Thirty meters below, indoors, this chimney is connected to the stove where the ballots were burned and at the same time to another which produced either black or white smoke.  Cylindrical in form, and one meter [three feet three inches] tall by 45 centimeters [18 inches] wide, the cast-iron stove used to burn the ballots was utilized for the first time during the conclave in 1939 that elected Pius XII.  The dates of the following conclaves (1958, 1963, 1978, 1978 and 2005) are engraved on it along with the date 1939.  The other stove, rectangular in form but with similar dimensions, which was used for the first time in April 2005, makes it possible to produce smoke thanks to an electronic system.  The tubes leaving the two stoves combine about two meters [six feet] above the floor to make one chimney.  A special system of electrical resistors and ventilation ensures improved evacuation of the smoke upwards.

(Sources:  VIS/Apic/Imedia/KTO – DICI no. 272, dated March 15, 2013)

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