On Sat, 14 Nov 1998, Mike Yates wrote:
> You might be interested in Peter Schmitt's work in Tanzania. There is
> very little evidence there too as to how far back bellows were used, but
> the archaeology does indicate a very slow rate of change in technology.
> He demonstatrated that the valve-less bellows used in East Africa up to
> the beginning of this century are actually advantageous because air is
> better pre-heated by being occillated in the tuyeres. He found that the
> longer tuyeres and more simple bellows, than those used in Europe in the
> BC era, apparently produced better blooms at much higher temperatures.
>
By complete coincidence, I just finished writing a long review of Peter
Schmidt's _Iron Technology in East Africa_ for the Journal of Field
Archaeology, so his data have not yet been erased from my tired old brain.
Mike is correct in stating that there is very little significant change in
this technology overa period of 2000 years, but that doesn't necessarily
mean that the bellows used in the ethnographic smelts observed by Schmidt
(valveless paired carved wooden pot bellows at each of the six tuyeres,
pumped by a standing human by means of sticks permanently attacked to the
skin diaphragm of each bellows chamber) were used that long ago - though
I suppose that they could have been. No archaeological evidence of bellows
was recovered by Schmidt's team. The only set of bellows from a
archaeological site in sub-Saharan Africa that I know of is a set of clay
bellows pots recovered in situ from a furnace excavated by Peter Shinnie
at Meroe, and dated, I believe, to the 4th century AD. The reference is:
P. Shinnie and F. Kense (1982) Meroitic Iron Working, in N.B. Millet and
A.L. Kelley, eds., MEROITICA 6 (Berlin:Akademie-Verlag) pp. 17-28
----------------------
David J Killick
Associate Professor, Department of Anthropology
University of Arizona, Tucson, AZ 85721-0030
Phone (520)621-8685; FAX 621-2088
[log in to unmask]
http://www.mse.arizona.edu/faculty/killick.html
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