One of the most remarkable and novel discoveries in the last 400 years has been electricity. One may ask, “Has electricity been around that long?”

The answer is yes, and perhaps much longer, but the practical use of electricity has only been at our disposal since the mid-to late 1800s, and in a limited way at first. One of the early attractions that gained public attention was an electrically illuminated bridge over the river Seine during the 1900 World Fair in Paris.

The use of electricity may go back much further. While constructing a new railway in 1936 near Baghdad, workers uncovered what appeared to be a prehistoric battery. The discovery was known as the Parthian Battery and was believed to be 2000 years old, dating back to the Parthian period. The battery consisted of a clay jar filled with a vinegar solution. An iron rod surrounded by a copper cylinder penetrated into the liquid and produced 1.1 to 2 volts of electricity. 



Figure 1: Parthian Battery. Believed to be a prehistoric battery, a clay jar holds an iron rod surrounded by a copper cylinder. When filled with vinegar or electrolytic solution, the jar produces 1.1 to 2 volts. The Parthians (circa 250 BC)
might have used this battery for electroplating.

Not all scientists accept the Parthian Battery as being a source of energy because the application is unknown. It is possible that the battery was used for electroplating, such as putting a layer of gold or other precious metals to a surface. Figure 1 illustrates the Parthian Battery.

The earliest method of generating electricity occurred by creating a static charge. In 1660, Otto von Guericke constructed the first electrical machine consisting of a large sulphur globe which, when rubbed and turned, attracted feathers and small pieces of paper. Guericke was able to prove that the sparks generated were electrical in nature. The first practical use of static electricity was the “electric pistol” which was invented by Alessandro Volta (1745-1827). An electrical wire was placed in a jar filled with methane gas. By sending an electrical spark through the wire, the jar would explode. 

Volta then thought of using this invention to provide long distance communications, albeit only one Boolean bit. An iron wire supported by wooden poles was to be strung from Como to Milan, Italy. At the receiving end, the wire would terminate in a jar filled with methane gas. To signal a coded event, an electrical spark would be sent by wire that detonated the electric pistol. This communications link was never built.



In 1791, while working at Bologna University, Luigi Galvani discovered that the muscle of a frog contracted when touched by a metallic object. This phenomenon became known as animal electricity — a misnomer, as the theory was later proved. Prompted by these experiments, Volta initiated a series of experiments using zinc, lead, tin or iron as positive plates; copper, silver, gold or graphite served as the negative plates.

Early batteries
Volta discovered in 1800 that certain fluids would generate a continuous flow of electrical power when used as conductors. This discovery led to the invention of the first voltaic cell, more commonly known as a battery. Volta discovered further that the voltage would increase when voltaic cells were stacked on top of each other. Figure 3 illustrates such a serial connection.



In the same year, Volta released his discovery of a continuous source of electricity to the Royal Society of London. No longer were experiments limited to a brief display of sparks that lasted a fraction of a second. A seemingly endless stream of electric current was now available. 

France was one of the first nations to officially recognize Volta’s discoveries. France was approaching the height of scientific advancements and new ideas were welcomed with open arms, much to the support of the country’s political agenda. By invitation, Volta addressed the Institute of France in a series of lectures at which Napoleon Bonaparte was present as a member of the Institute.