A platform is then built of clay, about six feet in length by
three feet in height and width.
A small well is formed in the centre of the platform, about
eighteen inches in depth and diameter, egg-shaped.
A few inches from the bottom of this well is an air-passage,
connected with a pipe and bellows.
The well is then filled with alternate layers of charcoal and
pulverized iron ore; the fire is lighted, and the process of
smelting commences.
The bellows are formed of two inflated skins, like a double
"bagpipe." Each foot of the "bellows-blower" is strapped to one
skin, the pipes of the bellows being fixed in the air-hole of the
blast. He then works the skins alternately by moving his feet up
and down, being assisted in this treadmill kind of labor by the
elasticity of two bamboos, of eight or ten feet in length, the
butts of which, being firmly fixed in the ground, enable him to
retain his balance by grasping one with either hand. From the
yielding top of each bamboo, a string descends attached to either
big toe; thus the downward pressure of each foot upon the bellows
strains upon the bamboo top as a fish bears upon a fishing-rod,
and the spring of the bamboo assists him in lifting up his leg.
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