While touring in the Kontagora Emirate in 1938, I passed through the village of
Madara, close to Madan, and was interested to see iron being smelted in the simple blast-furnace
|Iron-Smelting Blast Furnace|
The drawings are to scale from photographs taken at the time. However, as the
furnace was working, dimensions of the furnace-chamber are estimates only.
The furnace-chamber itself (1) was a small pit, oval in cross-section, measuring about
65 cm from front to back and 40 cm from side to side at ground level (2) and tapering to
a depth of perhaps 90 cm.
Straddling the pit was a man-high clay wall (3), reinforced at the sides with built-in
poles (4). This wall supported the bellows (7) and shielded the bellows-man from the
heat of the furnace. Built into its base at one side was a pair of recesses (5) containing
ten pebbles used as tallies - of these more anon. On the face of the wall were decorative
mouldings (6), perhaps indicative of the sex attributable to an entity giving birth to iron.
The blast was provided by a pair of bellows (7) consisting of two large earthenware
pots, each with its mouth closed with a diaphragm of goatskin, and its base fitted with a
spigot. As I recall, the diaphragm had a loop for the bellows-man's hand, and a valve controlled
air-inlet, with the valve having a looped thong for his thumb. The two bellows
were operated by pumping the two diaphragms in opposite phase, with the thumbs
controlling the two air-valves.
The bellows were held in place against the back of the wall by a bolster of clay (8)
and two forked poles (9), with the lower end of each pole (not shown) being anchored to
the ground with a heavy stone. The bolster also served as the bellows-man's seat.
The blowpipe (10) was cemented into place in the furnace-chamber with clay, and the
spigots of the two pots were cemented into its top, also with clay. (Blowpipes were made
by moulding clay round a slender bundle of long grass stems; this would burn out during
the subsequent firing to leave a clear bore.)
In operation, the furnace was charged with a mixture of precisely measured amounts
of ore and charcoal, and each time it was so charged one of the ten pebbles already
mentioned was moved from one tally-recess to the other. When all ten pebbles had thus
been transferred, the furnace was left to cool, and the pig of iron extracted.
The whole structure had a bare conical roof-frame over it; presumably the thatch had
been removed for the dry season lest it ignite in the heat of the furnace.
Ore was said to be mined from a nearby ridge.
In extensive travelling, this was the only instance of its kind that I came across.
Presumably the industry was dying out in the face of imported ironware, and in the face
of the ready availability of scrap-metal from old motor-vehicles, etc. A few months after
passing through Madara, for example, I saw metal-workers in Kano making excellent
razors from the high-grade steel of the spokes of wire-spoked car-wheels.