Furnace

In Slavic Power, the furnace is used to heat items. When a furnace gets constructed, you have to put it in your inventory - this causes a new window to pop up, where you can control the furnace.

For a quick tutorial on using the furnace, see Using the Furnace in Slavic Power.

Construction
A furnace can be both constructed from and disassembled into 16 iron.

Use
When you put the furnace in your inventory, a new window appears, where there is an icon of a flame, and an item slot below. This item slot is the fuel slot, where you can insert a fuel that will either add energy to the furnace, or keep it at a steady level. If you move an item onto the flame and click, the item will be heated. To initiate the fire, put a match in the flame.

Flammability
Every item has a property called flammability, which is usually 0%. But some items, for example a match, have higher flammability and they prevent the flame from being extinguished - these items should be put in the fuel slot. Some items have flammability of over 100%, meaning that they actually increase the flame power. Others, such as a log, have a flammability of 100%, meaning that they keep the flame at a steady level.