综合写作
In 1938 an archaeologist in Iraq acquired a set of clay jars that had been excavated two years earlier by villagers constructing a railroad line. The vessel was about 2,200 years old. Each clay jay contained a copper cylinder surrounding an iron rod. The archaeologist proposed that vessel were ancient electric batteries and even demonstrated that they can produce a small electric current when filled with some liquids. However, it is not likely that the vessels were actually used as electric batteries in ancient times.
First of all, if the vessels were used as batteries, they would probably have been attached to some electricity conductors such as metal wires. But there is no evidence that any metal wires were located near the vessels. All that has been excavated are the vessels themselves.