When we think about the birth of electricity, names like Benjamin Franklin, Thomas Edison, and Nikola Tesla might come to mind. But if we venture even further back in time, we stumble upon a curious artifact known as the Baghdad Battery.
This ancient piece, found in the vicinity of modern-day Iraq and believed to date back to the Parthian or Sassanid era (between 225 BC and AD 650), challenges our understanding of technological development. It’s a story that connects the ancient world with our modern one in a fascinating tale of science and history.
Discovery of the Baghdad Battery
The story of the Baghdad Battery begins in 1936. German archaeologist Wilhelm König discovered a set of 12 peculiar artifacts in the basement of the National Museum of Iraq. The artifacts, assumed to be about 2,000 years old, consisted of terracotta pots with a copper cylinder and a single iron rod inside.
Each “battery” was about 14 cm high, with a one-inch-wide mouth. The copper cylinder, carefully soldered with a 60-40 lead-tin alloy, encapsulated the iron rod. Evidence of an acidic residue such as vinegar or wine in some of the pots led König to propose that these were ancient electric cells.
The theory suggests that when the jars were filled with an electrolytic solution (like vinegar or lemon juice), they produced a potential difference between the copper and the iron — about 1.1 volts. This setup is remarkably similar to a basic school experiment to create a simple voltaic cell.
The primary controversy lies in the purpose of these devices. Some researchers propose that these ancient cells powered electroplating objects with gold. Others suggest a more spiritual role, possibly linked to pain relief. The sensation of a mild electric shock could have been interpreted as a divine intervention or magical experience.
Debates and Controversies
The theory of the Baghdad Battery as a tool for electroplating or electrotherapy is not without its critics. Skeptics argue that there’s no recorded evidence that ancient people had knowledge of electricity. Furthermore, there is no evidence of wires, conductors, or additional devices that could demonstrate a practical application for this alleged ancient technology.
Another point of contention lies in the design. If the intent was to generate an electric current, the iron rod would have quickly corroded due to the acidic solution. However, some of the recovered artifacts still have uncorroded iron rods, suggesting they might never have been used as proposed.
Source: “Was the Baghdad Battery really a battery?” — BBC Science Focus