Page 35 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

skin, especially in cuts or puncture wounds, and may have been beneficial in acupuncture, with
the current applied to the needle, or may have been of ritualistic use in shamanism. The current
C
from electric fish was already in use by the first century E . in the Greco-Roman world as an
analgesic. In the mid-first century, Scribonius Largus first recorded the practice of applying the
fish Torpedo ocellata as an analgesic for headaches and gout. Keyser (1993) speculates that wet-cell
batteries may have functioned as substitute ichthyoelectroanalgesia or have been used for thau-
maturgical effect. Eggert (i996) observed, however, that König (i938) had referred to similar
finds from Seleucia (bronze cylinders containing papyrus relics) and from Ctesiphon (rolled
bronze sheets). These latter Sasanian finds were discussed in detail by Paszthory (1989). Eggert
draws attention to the problem of sustaining the flow of electric current. The small initial cur­
rent is due to the reaction of oxygen dissolved in the electrolyte. Since most of the parallels to
the finds from Khuyut Rabbou'a are not tightly closed copper cylinders, the whole vase would
be filled with an electrolyte. The walls of the earthenware vase are porous, and oxygen from the
air could diffuse steadily into the electrolyte, which would help to sustain the current flow for a
longer period. Despite this possibility, Eggert agrees with Paszthory that it is more probable that
the containers may have represented magical jars for blessings or incantations written on parch­
ment or papyrus, which would account for the discovery of papyrus fragments in some of these
containers. The work by Eggert (i996) should be consulted for the most current bibliography of
thirty papers that these mysterious objects have generated.
There is a natural tendency for writers dealing with chemical technology to envisage these
unique ancient objects of two thousand years ago as electroplating accessories (Foley 1977), but
this is clearly untenable, for there is absolutely no evidence for electroplating in this region at
the time, and the medical or magical world must be invoked.

Early technologies with The electropotential difference between iron and copper is
copper and iron important in displacement reactions: copper, for example can
be displaced from solution by iron; an iron rod immersed in a
solution of copper sulfate rapidly becomes covered with a thin coating of dull reddish yellow
copper metal. Corfield (1993), in reviewing the methods used to coat iron with copper, mentions
that in 1873 Spon had already described numerous methods for the plating of iron with copper
for commercial use; of course, this kind of plating was already known in medieval times as well.
The first reference to this kind of process in Europe was in the eighth-century Lucca manu­
script, Compositiones variae, from Lucca, Italy (Johnson i94i), whose antecedents derive from
a Spanish text dating from 725, which in turn is descended from a manuscript dating to 650,
which is a transliteration from an even earlier Greek text (Burnham 1920). The Lucca manu­
script therefore contains information that may trace its lineage back to the early centuries
C E . One recipe discusses the treatment of an iron surface with a mixture of corrosive salts

C H A P T E R O N E
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