Paul K. Dickman wrote:
"Joseph Gwinn" wrote in message
...

http://en.wikipedia.org/wiki/Electroplating#History

The articles I read many years ago were talking about ancient Egypt or
China, at least 1000 years before the 1800s, well before the invention
of the battery by Volta in Italy. What was described was a battery and
plating cell all in one. It might have been for copper plating. It was
clear that ancients did not understand why the thing worked, only how to
replicate it.

Joe Gwinn


Your probably thinking of the Baghdad batteries.

These were ancient ceramic jars with a tar seal and a sheet of copper and an
iron rod inside.

Speculation in some circles goes something like this:

"What the hell are these things?"
"Could be a battery."
"What the hell did they need a battery for, they didn't have any transistor
radios?"
"They must have invented electroplating!"

Anyone who has made a battery for a science fair project knows that iron and
copper have only about 3/8 v potential between them and make a pretty crappy
battery.

If you wanted to do any plating, you would need at least a dozen of them in
series. If the ancient Mesopotamians knew the difference between series and
parallel.

Paul K. Dickman


Apparently they did know the difference:

"In 1936, at Khujut Rabu'a near Baghdad, was found a small pottery jar, about 5-1/2
inches high and 31 inches in diameter. Inside was a cylinder of thin copper, closed
by an asphalt plug. Inside the cylinder was a rusted iron rod.
Similar jars, without the metal cylinders and rods, had been found at the ruins of
Seleucia-on-the- Tigris, twenty-four miles below Baghdad.
Three larger jars containing respectively ten copper cylinders, ten iron rods, and ten
asphalt plugs, not yet assembled as in the Khujut Rabu'a jar, turned up at Ctesiphon,
across the Tigris from Seleucia.
All these objects date approximately from Roman Imperial times. The only use that
anybody has been able to conceive for them is as battery cells for electroplating small
metal objects with gold.
It has also transpired that the silversmiths of Baghdad, within the present century,
used a similar apparatus for gold-plating their works. Those who knew about this
method long assumed that the silversmiths had learned their electroplating from western
sources. Although ar*cheologists are not yet agreed about the mysterious jars, we must
at least consider the strange possibility that electroplating was discovered in Iraq in
ancient times; that, despite the ravages of the Mongols in + XIII, this technique
survived down to the present century; and that, nevertheless, it failed to spread
to other lands, presumably because the metal workers kept it secret."

"The Ancient Engineers", L Sprague Le Camp, 1960

Tom