BELLOWS. An ancient device for fanning the flames of the fires of the smelting furnace. The Egyptian type of bellows was operated by the feet, as one alternately trod on two inflated skins. This created a forced draft by means of reed tubes tipped with iron; the air thus jettisoned into the glowing fire caused the flames to burn more brilliantly and hotly. As each skin was exhausted of its supply of air, the workman would raise it by a cord attached for that purpose and inflate the skin again. This process was then repeated as many times as was necessary. See Jer.6.29.

BELLOWS, appears only once in KJV and RSV in Jeremiah 6:29 for Heb. מַפֻּחַ, H5135, a maqtal participial substantive from the verb נָפַח, H5870, the common Sem. verb “to blow,” “to breathe.” The term appears in the Ugaritic text II AB (No. 4) lines 24, 25. The poem states “Hyn goes up to the bellows, in the hands of Hss (are) the tongs.” In the earliest smelting installations of the ancient Near E the furnaces were aligned to take advantage of the prevailing winds to fan the flame and increase the temperature. Small hand bellows of skins with wooden frames were apparently used for making bronze and the much harder iron. The art of metallurgy was passed from the peoples of Anatolia to the Semites of the fertile crescent. The word for “bellows,” however, indicates that the tools of the trade were known to the peoples of Syria-Pal. from at least 2000 b.c. The text of Jeremiah contains many such rare words found only in Ugaritic texts outside of the Bible. Such demonstrates that the true antagonists of the worship of Jehovah were resurgent followers of the Canaanite Ba’al and the cult’s elaborate rituals.

International Standard Bible Encyclopedia (1915)

bel’-oz, bel’-us: The word occurs once only in English Versions of the Bible, in Jer 6:29, where the prophet is predicting the coming of the destroyer (verse 26), "a great nation" from "the north country" (verse 22), down upon Israel, because "all of them deal corruptly" (verse 28). "The bellows blow fiercely; the leads is of the fire." Here the imagery is drawn from the refiner’s art, and the "bellows" are those used to make the refiner’s fires burn fiercely.

See CRAFTS, II, 10.