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The strange case of the exploding trousers

A cautionary tale

Traditionally, we have relied on our pants to do many things: keep us warm, preserve our modesty, not explode. But if the old tales are true, we have not always been able to do this with absolute confidence – especially if we were farming in 1933 when flies on fire were just an occupational hazard.

The fullest contemporary account of the phenomenon comes from the Evening Post of April 21, 1933, which reported it in a multi-deck heading typical of the time:

Trousers Explode
Not Their Fault
Weed-killer Dangers
Sodium Chlorate

The second deck may seem tautological until you reflect how much trouble their pants have got people into over the years.

The writer of the story yields to no one in his facility with litotes and irony: “Not long ago, in a country township, a man’s pair of trousers exploded with a loud report. Fortunately, the owner was not in them at the time.”

He or she is not one for leaving the reader in suspense, however, going on quickly to explain: “This strange behaviour of a quite respectable garment was due to the fact that its owner had been spraying sodium chlorate on ragwort.” And, inevitably, on themselves as well in the process.

Sodium chlorate was a widely used method for dealing with ragwort, a noxious weed. The writer explains the process in simple language, without getting too pyrotechnical: the moisture quickly evaporates from sodium chlorate, leaving residue in clothing or other matter, which will burst into flame from friction, a sudden blow or exposure to high heat – all stimuli that are likely to be encountered when working on the farm.

Smothering was not much of a remedy, as the oxygen necessary to feed a fire was already “present in… intimate contact with the material”.

The Post also claimed there had been at least two deaths from this phenomenon. “Certain modern inventions, like high explosives and flying machines, provide room for only one mistake, unless the experimenter is lucky” was the sombre conclusion.

Massey University historian James Watson examined the phenomenon in his widely reported 2004 paper “The Significance of Mr Richard Buckley’s Exploding Trousers: Reflections on an Aspect of Technological Change in New Zealand Dairy Farming between the World Wars” – tying it all to literate farmers, immigration policies, child labour and “the widespread drive for independence from farm workers and neighbours”. Well, you wouldn’t want to get close to a neighbour who could turn into a bonfire at short notice, would you?

Watson attended a ceremony at Harvard University where he was awarded an Ig-Nobel Prize for his research in 2005.

In 2006, the popular science TV show Mythbusters tested four substances to see whether they could turn any old pairs of trousers, no matter what their cut, into flares. One of these, although unnamed, was sodium chlorate, which was indeed shown to cause pants to combust.

Many a liar has almost certainly tried to blame the chemical for the fact their pants are on fire. However, we’re pleased to report that despite this spate of exploding trousers, “arson” puns – although there for the making – were few and far between in discussions of the phenomenon…

And there have been no recent fatalities. Ragwort, however, is still a problem.

This was published in the January 2018 issue of North & South.