Aboriginal fire plough and hearth.
© Science Museum / Science & Society Picture Library
If a stick is rubbed very quickly against another piece of wood, friction can make it hot enough to make tinder catch fire. In this Aboriginal fire plough and hearth from Australia, the stick or 'plough' is pushed along the groove towards the 'hearth'. Hot pieces of the stick jump on to the tinder placed in the hearth to make a flame.