Professor Frank James with Alessandro Volta's voltaic pile. Courtesy Royal Institution
Curator's Choice: In his own words... Professor Frank James, Head of Collections and Heritage at the Royal Institution chooses Alessandro Volta's Voltaic pile battery, made from zinc, copper and cardboard. Here he explains its history and scientific importance.
"I must have seen it before I came to the Royal Institution (RI), but it was only when I started working on the collections that I realised what an interesting object it is.
In 1814, Michael Faraday was assisting the newly retired RI Professor of Chemistry, Humphry Davy, on a European tour. They visited Milan, and while there they went to see Volta, who gave Faraday this battery.
I like to see that event metaphorically – in giving the battery to Faraday, Volta was passing on the torch of electrical research to the younger man.
The voltaic pile was born of a debate that went on between Volta and his peer Luigi Galvani regarding electricity and life. Galvani created a battery of frog's legs and perceived electricity in biological terms, whereas Volta said, "We can do this with inorganic materials," and then made his pile – the first electric battery – in order to prove it.
It's just plates of copper and zinc with blotting paper in between, piled up one on top of the other – that's why it's called a pile. Soak that blotting paper in acid and that's what gives you the continuous current.
This was absolutely critical, because up until that point, in 1795, when people talked about electricity, they were referring to static electricity; the sort you get in Leyden jars and electrostatic generators. That's a very high tension, high voltage electricity but with very low power, you really can't do anything useful with it. The voltaic pile allowed you to have a fairly low voltage but continuous, so you could actually put it to use.
This item is also a great example of the kind of workmanship that once went into scientific apparatus, a situation that was soon to change. Up until the time the Royal Institution was founded, in the late 18th, early 19th century, scientific apparatus and instruments were all produced to a very high standard, with very high quality finishes.
But from about 1800, when the voltaic pile was made, there's a real change. Scientific instruments were still finely crafted, using lots of polished brass and glass and turned wood and so on, but those sorts of designs become increasingly confined to instruments.
Meanwhile, scientific apparatus used to explore nature, while effective, became increasingly crude in design. You can see this very clearly in our displays – at one point, we have some very nice early 19th century wooden material right next to later items which are extremely rough and ready.
The voltaic battery provided a fairly low voltage, but the power was continuous, so you could actually do things with it. Humphry Davy was the first person to start to understand what you could use these batteries for, in the RI in 1808. He discovered sodium potassium using batteries based on the same principal.
In the case where the voltaic battery is located, we have another much bigger battery on display underneath, made by Davy six or seven years later – one of the batteries he used to isolate sodium and potassium and other folk elements that he worked on. It opened up a whole new field of science that simply didn't exist before."