The eccentric engineer

E&T on the little-known 18th century 'war' of the knobs and points.

Benjamin Franklin, when not busy signing the American Declaration of Independence, was an electrical experimenter. One of his great contributions to the modern world has been his invention of the lightning conductor - but what is less well known is how this led to a war.

Franklin's experiments had shown that conductors with a sharp point discharged electricity more quietly and over a greater distance than blunt conductors. This gave him the idea of putting sharp conducting iron points on tall buildings and attaching these to a wire passing to earth and so, as he put it,"drawing the electrical fire silently out of a cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible mischief".

Soon the Philadelphia State House was sporting its own gilded iron lightning conductor, and the concept crossed the Atlantic to be taken up by the owners of churches with large spires and people working in gunpowder magazines.

But not everyone was so struck by the idea. French electrical experimenter Abbé Nollet warned the French Academy of Sciences: "I believe that [lightning conductors] are more suitable to attract the fire of thunder to us than to preserve us from it."

In England, the invention was taken more seriously and, after St Bride's on Fleet Street was badly damaged by a lightning strike, St Paul's Cathedral was fitted with one of Franklin's 'points'. The government was also interested and a Royal Society commission suggested the installation of pointed conductors on the roof of the gunpowder magazine of the Board of Ordnance House at Purfleet, which was duly done.

Then disaster struck. In 1777, the Purfleet magazine was hit by lightning, and the few bricks that were dislodged in the strike were enough for dissenting committee member, Benjamin Wilson. This proved, he said, that his idea of using rods with 'knobs' on the end was superior to Franklin's 'points'; points would actually encourage "the very mischief we mean to prevent". The learned men of the Royal Society conducted their own experiments and disagreed, much to Wilson's fury.

Now this appears to have all the makings of a pretty minor back-room scientific feud. But this was the late 18th century and Franklin was one of the signatories of the American Declaration of Independence, over which a war with Britain was then raging.

The supporters of 'points' and 'knobs' ludicrously became equated with the sides in the American War of Independence. To favour a 'point' was to support the rebels fighting against their true king, while to prefer a 'knob' was an act of patriotic British duty. As Wilson put it, Britain was duty-bound to "discard the invention of an enemy".

And the vaguely unstable King George III agreed with him. He ordered all 'points' be removed from government buildings and replaced with 'knobs' forthwith, although, as with many of George's orders, it's unclear if it was ever carried out. The King further attempted to force the Royal Society to reverse its committee's decision on the matter, but a very brave president of the Society, Sir John Pringle, when summoned before the irate monarch, boldly stated: "My duty, sire, as well as my inclination, would always induce me to execute your Majesty's wishes to the utmost of my power, but I cannot reverse the laws and operations of nature." To thank him for his disarming honesty, the King promptly had him fired both from his job at the Royal Society and as a Royal Physician.

Across the Atlantic, Franklin, who famously hated arguments, simply noted wryly that the King's changing of 'points' for 'knobs' was "a matter of little importance to me. If I had a wish about it, it would be that he had rejected them altogether as ineffectual, for it is only since he thought himself and his family safe from the thunder of heaven, that he dared to use his own thunder in destroying his innocent subjects."

I need hardly add that the argument on both the shape of lightning conductors and the fate of the American people was eventually decided in Franklin's favour.

Winner of the issue 16 caption competition was Keith Workman with 'The mountain rescue committee were impressed, but decided to stick with St Bernards after all'.

This issue's prize is provided by leading tool supplier Facom. 'Kit Micro-tech' is a handy set for any engineer working on IT or office equipment. The hard-wearing case contains five screwdrivers, a torch, a mirror, two pairs of pliers, two blades and a blade handle, a wrench and two pairs of tweezers. For more information on Facom's extensive tool ranges visit [new window].

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