Wade Blocker on sun 27 may 01
Dear Clayarters,
I would like to share with you part of an interesting article on CT in
the archaelogic study of ancient Greek ceramics and will quote from this
study.
The first pottery was made about 6000 BC.At first the pottery was made
without a potters wheel. About 2500BC the slow turning wheel was invented
in the Levant. The Greeks introduced the fast turning potter's wheel in
900BC.
Thanks to their excellent clay,ancient Greek potters were able to turn
pottery with highly sophisticated shapes on their wheels.This article
shows that the use of CT makes more accurate, less time-consuming
profiles of Greek ceramics than is possible with the conventional profile
drawing. Up until the introduction of molds for pottery production in the
last quarter of the third century BC, all pottery was hand made.
To make a profile drawing, the thickness of the walls was measured with
calipers, usually on one side only. Generally the opposite side was a
"mirror image" of the measured side, giving a false impression of a
symmetric object.This method is therefore inaccurate and also time
consuming, and does not work for closed shapes whose narrow necks do not
allow the introduction of calipers.
With the use of CT it is possible to visualize the inner structure of
the wall,draw conclusions about the quality of the material used and
insights into pottery making techniques.eg. CT scans reveal air bubbles in
the walls, a finding that indicates poor handling of the clay. CT also
shows if any restoration has been made.or whether the pot is entirely
authentic.
eg. for protocorinthian aryballoi the theoretic explanation was that the
foot, neck and mouthplate ware always attached as separate parts. In some
cases CT scans show no assembly, but that the use of tools was employed to
create the desired shape.
CT can also provide clues about how a ceramic piece was used. eg the
"miracle" jar is
double walled and thus contains two chambers. Between these chambers and
the outside ,there is a system of channels. Experimental studies revealed
that when the jar was put in hot water, a vacuum was created in the inner
chamber. By placing the heated pot against a woman"s breast, milk could be
extracted and collected.
This article appears in RadioGraphics 2001;21:315 321,from the department
of Radiology,Academic Medical Center,University of Amsterdam,Jansen et al
Hope you enjoy reading this. Mia in hot ABQ
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