No, Kerosene did NOT save the Sperm Whale

How we carried on exploiting sperm whales long after the conventional wisdom said we'd stopped. Forgotten Material #1

Photo: Gabriel Barathieu

There are many extraordinary creatures in the world, but few are quite as extraordinary as the sperm whale.

These vast, enigmatic mammals have long fascinated and terrified humans. Don’t take it from me, take it from Herman Melville. But in this case the reality is even more fascinating than the myths.

Capable of diving thousands of feet beneath the waves for over an hour at a time, the sperm whale has perhaps the most exotic diet on the planet. As the biggest toothed predator on earth, it feasts on mysterious bottom-dwelling sharks, skates and, most notably of all, the giant squid - another of the world’s least well-understood animals.

Superlatives abound. Sperm whales have the biggest heads (in proportion to the rest of their bodies) of any large animal. A typical sperm whale might be one-third head. And while much of what is to be found inside that head is brain (yes, sperm whales are also notable for having the largest brains on earth) even more space is given over to something else: spermaceti.

Spermaceti is the name given to this very unusual organ as well as the waxy oil it produces. Even today no-one is entirely sure what function the spermaceti serves. One theory says it has something to do with buoyancy, the other that it is for echolocation. What we do know is that it is one of those very unusual things - an organ unique to a single species (well, strictly speaking the three species of sperm whale).

Cross section diagrams of a sperm whale’s head, from Wikipedia

The upshot is that that enormous head contains within it a vast reservoir - somewhere between 2,000 and 3,000 gallons in a male whale - of spermaceti oil.

Sperm whale oil is a very special oil, comprised of long chained molecules known as fatty esters. These things are quite rare in the wild, to the extent that there are few other naturally-occurring substances which behave quite the way sperm whale oil does.

Humans are ingenious at devising all sorts of random uses for all sorts of random substances (come to think of it, that’s pretty much the subtext of Material World) and so it was for this oil. Sailors soon realised that it worked brilliantly as a lubricant for their clocks and watches (its viscosity doesn’t change much whatever the temperature - yet another unusual feature of this unusual substance). But eventually an even more popular use-case was discovered: as a fuel for lanterns.

This of course was long before the invention of electricity and most other light sources had severe drawbacks. Tallow and other forms of oil derived from animal fat burnt with a dim, smoky flame. Whale oil, by contrast, provided an excellent light and produced little smoke. While tallow burnt with a foul smell, whale oil produced no unpleasant odours. And so, in the early days of lighting, spermaceti became a sought-after fuel for lanterns.

If you have read much about the history of lighting - or for that matter Material World - you will know what happened next. Mankind began to hunt and slaughter sperm whales in vast quantities. People panicked that they would soon be extinct. Then, in the middle of the 19th century, humankind worked out how to make kerosene from crude oil, and it rapidly replaced whale oil in lanterns. Since kerosene burnt six times brighter, there was no need any longer to kill whales for lighting.

As William Nordhaus, the Nobel prize-winning economist, put it in his seminal paper on lighting, as well as interviews since, kerosene “saved the whales”. It’s a great, counterintuitive story: look! Fossil fuels saved the world (until they threatened it a couple of centuries later)! And so this Nobel prize winning version of history has been trotted out pretty much everywhere ever since, including, I should acknowledge, in my own book. It’s become a part of the conventional wisdom.

But there’s a problem with the Nordhaus version of events. It is plain wrong.

Crude oil did not save the whales. While it’s true that whale oil fell out of favour as a fuel for lighting after the discovery of kerosene, the number of whales being killed in the following years didn’t fall to zero. On the contrary, it rose. A lot. Look:

The bars are the number of whale catches around the world each year from the early 19th century to the 1980s. Data from this paper.

The chart tells the story. As you see, it’s pretty stark. Far from dropping to zero after the widespread adoption of kerosene, whale oil catches only fell a bit before picking up dramatically in the 20th century. Many multiples more died in the 20th century, long after Nordhaus suggested they had been saved, than in the 19th. Why?

The story features in Jean-Baptiste Fressoz’s brilliant book More and More and More, which I highly recommend as a companion piece to Material World. As he explains, it turns out lighting oil wasn’t the only use we found for spermaceti.

As I mentioned earlier, right from the start whale oil had other uses, beyond lighting. It was used to grease naval clocks, as well as being deployed in pharmaceuticals, paints and explosives. And when added to conventional petroleum oil, spermaceti transformed a good engine lubricant into the world’s finest engine lubricant. Thanks to those esters, whale oil-infused lubricants were incredibly good at reducing friction. And so while whales were no longer hunted for lighting fuel, they became even more prized in the 20th century for a somewhat more obscure use no-one spent much time thinking about.

And since whaling technology had come along so much since the 19th century - with powerful diesel engined vessels equipped with ever more lethal harpoons and even onboard processing plants, allowing sailors to drain the spermaceti out of their catches at sea rather than having to bring them back to land - sperm whale populations were ravaged long, long after the discovery of kerosene.

Indeed, that chart above slightly understates the full scale of the onslaught in the 20th century, because quite a lot of the whaling fleets from Japan and the Soviet Union weren’t declaring all their catches to the International Whaling Commission. Adjusted estimates are somewhat higher.

Fressoz’s point is that far from saving the whales…

Actually, petroleum increased the demand for whale oil: top-of-the-range lubricants for gearboxes and machine tools used to contain between 5 and 20 per cent whale oil. Until the mid-1970s, aircraft turbojet engines were lubricated at least in part with whale oil.

But this story ends somewhat happily, because that chart really does show a dramatic fall to close to zero in recent decades. So what really saved the whales? Well, the answer is first, the whaling bans which, across most of the world, made it illegal to hunt these whales (a few countries refused to sign up, but catches have nonetheless dropped dramatically in recent years). And, in the face of this enforced shortage of whale oil, lubricant manufacturers and other users of whale oil had to try to find a satisfactory substitute.

Lo and behold, in the 1970s there was a sharp rise in research and development spending on esters. Chemists worked out how to create synthetic alternatives. Eventually, however, it was the natural world that provided the best substitute: the oil from the jojoba tree, which has most of the same properties as whale oil. All of a sudden, an obscure plant, never much cultivated, helped fill the gap left by spermaceti.

So in one respect, Nordhaus was right: technology did eventually save the whales. But a) it happened more than a century later than he suggested, by which point whale stocks were much lower than in the 1860s, b) the technology in question wasn’t derived from crude oil and c) it was only developed in response to a government-enforced ban on whale hunting.

These might seem like minute distinctions, but they all matter, and perhaps it’s worth reflecting on this in the 2020s. After all, here we are at another inflection point, with a lively debate between those who believe technology, left more or less to its own devices, will deliver the solutions to climate change and those who believe nothing will happen without government intervention.

For a long time that Nordhaus-fuelled conventional wisdom, that kerosene saved the whales, left one with the impression that technology alone could save the day. But now ponder the corrected story of the whales and you’re left with, well, if not the opposite impression, then a considerably more nuanced conclusion. And I’ve been taught another lesson: always fact check Nobel laureates!

Anyway, as promised, this was the first of a series of posts about “forgotten materials” - substances we convinced ourselves we had stopped exploiting even as we were mining massive amounts of them. There’s quite a few other interesting examples to come in the weeks ahead.

UPDATE 31 Dec: A couple of readers have pointed me towards this absolutely excellent paper on precisely this topic from Richard York a few years ago. I hadn’t read it, but I wish, in hindsight, that I had. Please do send me further thoughts/links via the comments or social media.