Firebox
Cast-iron firebars over a refractory rim. Charge it with coke, coal or charcoal - one fuel at a time - and the flame is drawn across the hearth beside it.
Charge it through the Charge Door in front of it. A bed lit and left to thin past half its capacity is the one way a reverberatory furnace goes out on its own, so recharge it before it runs that low.
See Coke and fuel and Furnaces and heat.

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topMade by
| any Refractory brick x 2 | any Refractory brick x 2 | any Refractory brick x 2 |
| Rod (Iron or Steel) | Rod (Iron or Steel) | Rod (Iron or Steel) |
| any Refractory brick x 2 | any Refractory brick x 2 | any Refractory brick x 2 |
| Firebox | ||
Needs: 12 any Refractory brick, 3 Rod (Iron or Steel); makes 1 Firebox
Amounts are the mod's defaults; the recipe-cost level changes them (see recipe cost levels).