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"The oldest form of blast heating apparatus, applied by Neilson, consisted of a tubular rivetted boiler plate heating vessel, mounted in a brick chamber OOOO, and heated by a fire underneath fed through the door D, the waste gases from the fire passing out at the far end of the chimney. Crescent-shaped partitions p, p, p inside the heater caused the current of air from the blowing engine which entered at B to take a serpentine course as indicated by the arrows, finally passing off at S to the furnace." — The Encyclopedia Britannica, 1893

Hotblast Stove

"The oldest form of blast heating apparatus, applied by Neilson, consisted of a tubular rivetted boiler…