FUEL (Heb. אָכְלָה, H433, in the phrase, מַאֲכֹ֥לֶת אֵֽשׁ, food for fire [Isa 9:5, 19; Ezek 15:4, 6; 21:32]) used of fuel on the analogy that fire consumes material. The fuels of antiquity all were derived from vegetable hydrocarbons. Woods and barks were burned along with rushes, straw, twigs, sticks, thorn bushes, chaff and roots. The only animal material was dung, which burned slowly and gave off a detestable odor. The process of making charcoal certainly was discovered by the beginning of the 2nd millennium b.c., as it was used to gain the necessary temperature for the smelting of copper and the alloys needed to make bronze. Since many of the richer homes and temples utilized charcoal and the braziers upon which it was burned were imported, the OT has a number of foreign cultural-words which are used to describe them, e.g. Heb. כִּיר, H3968, (Lev 11:35); Heb. אַח, H279, (Jer 36:22, 23).