Bail hill; Bail hills; Bale
sometimes called balehill(s), bail hill(s), bale(s) or bayle(s)
A bolehill was a shallow furnace used when smelting Galena. It was a circular pit one or two metres wide, with a sloping base - so molten lead would form, collect and solidify in a pool. Around the edge was a wall with deliberate gaps in to allow the wind to fan the flames. These were often place on hilltops. Crushed Galena was placed on top of wood fuel. The fuel was set alight and as the ore was chemically reduced to lead (Pb) it was collected in the hollow. Bellows could be used to fan the flames.
Remains of bolehills are usually a circular burnt area of ground with bits of fuel and Galena in black soil and pieces of slag piled up on one side. Bolehills were usually used in the Medieval period in the 15th and 16th centuries, until they were replaced by shaft furnaces, which used water-powered bellows.
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