When killing small animals was fun

Like all specialists, scientists love to celebrate their superstars. It often falls to historians of science to point out that most progress is due less to famous individuals than to communities of quite ordinary people. No wonder they are often unfairly shouted down as party poopers as a result. Publishers of popular-science books also prefer heart-warming heroes to historical wisdom. The journalist Dava Sobel gave us a new one in her unexpected hit Longitude , an engaging account of how the previously little-known engineer John Harrison won a competition to design a clock that could tell the time reliably at sea. The book achieved the seemingly impossible by making horological history sexy. Ever since, science publishers have been asking: where's the next Longitude ?

Former curator Brian Bowers mines another rich historical source in the new edition of his biography of the English scientist and inventor Charles Wheatstone. Wheatstone appears to deserve no more than a place in the B-team of dead scientists. He is best remembered for something that he did not actually invent - the inappropriately named Wheatstone bridge, useful for measuring electrical resistance. He should, however, be much better known as one of those responsible for the development of the electrical telegraph - a device that sparked off a genuine technological revolution. Before it, the fastest communication was by semaphore or carrier pigeon.

This is a story of potentially huge popular appeal: the privately vivacious but publicly shy inventor who developed the truly revolutionary technology that presaged the internet; how he fell out with his entrepreneurial co-developer William Cook; how he beat the great Faraday to the invention. But Bowers is writing not for a general audience but for his peers, who will not be disappointed. Bowers is unfailingly meticulous and entirely accurate in his summary of Wheatstone as someone who began his career as an accomplished experimenter and later specialised in applying the research ideas of others. As a result of this specialisation, he often came up with brilliant new designs for sensitive and accurate apparatus.

It was Wheatstone who invented the variable electrical resistor, often known as the rheostat, Bowers reminds us. And it was Wheatstone who was the first to understand the principle of binocular vision, which led to the development of the stereoscope, second only to the kaleidoscope as the most popular scientific toy in 19th-century Britain. His work on acoustics led him to develop several musical instruments, all now thankfully forgotten except, alas, the concertina.

Bowers's biography is written in a style that now reads quite quaintly. He often refers to himself as "the present writer" and on one unfortunate occasion implies that an electrical engineer is certain to be a man. Likewise, his approach is to consider his subject quite narrowly, without examining its broader social and cultural context in much depth.

No such criticism could reasonably be made about Patricia Fara's accessible, pocket-sized account of the electrical experiments carried out by Enlightenment "scientists", as they were first dubbed in 1834. Fara entertainingly describes how experimenters caught the public imagination with electrical demonstrations devised and carried out by "electricians", a word coined by Benjamin Franklin in 1751. Franklin invented the lightning rod after famously extracting electricity from thunder clouds by flying a kite among them. He was widely celebrated for this, especially in France, which is ironic as he was not the first to do this experiment - it had been done a few weeks earlier by others in the French town of Marly.

The Leyden jar - a device invented in 1745 for storing and supplying electrical charge - enabled spectacular and enjoyable experiments, many of which would raise the eyebrows of health and safety inspectors today. In one demonstration, the Abbe Jean-Antoine Nollet discharged one of these jars in front of King Louis XV by sending a current through a chain of 180 Royal Guards, who jumped in the air one after another as the charge passed through them. A jar now on display at the Boerhaave museum in Leyden has an adjustable dial with four settings: detonating cannon, altering a compass needle, melting wire and killing small animals.

The chief strength of Fara's book is the way it combines telling anecdote with wise commentary. She is especially good at highlighting the social and economic forces that shape science in ways scientists are sometimes reluctant to acknowledge, at least in public. This modern approach makes An Entertainment for Angels a welcome addition to the Revolutions in Science series. The publisher, Icon, is to be congratulated on this but roundly admonished for depriving all of these richly informative books of an index.

Through Fara's compact rendering of the story of the Italian electrical pioneers Luigi Galvani and Alessandro Volta, we see how beastly scientists can be to each other as they compete for glory. We also appreciate the difficulty of understanding past discoveries from today's point of view. Whereas Galvani thought he had discovered "animal electricity" in frogs, scientists today would prefer to describe his work as a demonstration of how an electric current is generated when two metals touch in the frog's conducting environment.

However, although Fara presents us with numerous tasty and well-presented historical morsels, we end the book hungry for something substantial, aware that we have just dined on canapés. This highlights the main achievement of Longitude - it was an appetiser that somehow contrived to be as satisfying as a main course. That may be why it has been so hard to follow.

Graham Farmelo is head of science communication, Science Museum.