Age of Invention: Lessons from the Rise of Coal

You’re reading Age of Invention, my newsletter on the causes of the British Industrial Revolution and the history of innovation. This edition went out to over 25,000 subscribers. To support my work, please upgrade your subscription here:

I’ve got a really big post coming up, which I’d hoped to share with you last week. It’s one that had started as “just a quick post” but soon became an obsession as I discovered more and more: much like my series uncovering the forgotten origins of the steam engine, on how we kept forgetting how to cure scurvy, or my personal favourite ever posts on whether or not the printing press was banned in the Ottoman Empire (Part I, Part II). I don’t want to give too much away — especially as the post will start with a riddle — but I hope you’ll forgive my relatively infrequent posting of late while I try to get it all researched and written up.

In the meantime, however, I’d like to share some work I did for the UK’s innovation agency, Nesta (originally the National Endowment for Science, Technology and the Arts when it was set up in 1998, but the acronym has since eaten its host). To inform Nesta’s work on the transition to renewable energy and what it might be used as an opportunity to create energy abundance, they commissioned me to research previous energy transitions — specifically, the original transition to burning coal.

I don’t often take research commissions, mainly as I ought to concentrate on finally finishing my book, but I do when it gives me an excuse to pull on some dauntingly tangled-looking research threads that I really need to tie up, but hadn’t yet braved — a way of bumping things up my long to-do list of topics I know I need to cover and actually getting them crossed off.

Here are a few key things that I hadn’t really fully appreciated until undertaking this particular commission, though each has provided even more threads I still need to pull on:

ONE. The transition to coal was started by finding ways to exploit the lower-grade, cheaper and more sulphurous coals: initially by finding ways to burn it in people’s homes that would not leave everyone crying and coughing from the stinking fumes; and then with the expanded supply of even the lowest-grade coals making it cost-effective to do things like boil seawater in pans to make salt. The very lowest-grade coal was termed simply “pan coal”. While I’m pretty certain that these innovations were responsible for much of the rise of coal — coal-fuelled salt pans were even the foundation of the Scottish Lowlands economy going into the eighteenth century — the actual inventors involved are still a bit of a mystery. It’s something I need to return to, as “lots of anonymous people just invented through trial and error and adaptation” just doesn’t cut it for me — I’ve never found such stories to be true upon closer investigation.

TWO. Nobody ever talks about lime! Lime was one of the few things burnt with coal since ancient times, but largely to produce mortar for building. The increased availability of cheaper coal in the sixteenth century, however, meant that lime also soon found much wider use as a soil acidity regulator, as well as to control some pests and improve the absorption of fertilisers. It was especially favoured for sandy soils, allowing the conversion of barren heaths to agricultural land by increasing the soil’s water retention.

Yet lime is a huge blind spot for economic historians, despite it increasing the productivity of what was still by far the largest portion of the economy: agriculture. I have a rough and ready test of whether economic historians are paying enough attention to an industry, which is to look up the word in Stephen Broadberry et al.’s British Economic Growth 1270-1870, most scholars’ go-to resource on how historical British output is estimated. Lime is mentioned only once, and only as an input to the construction industry, for mortar. We should know more about lime’s impact.

THREE. Coal, through its various effects on agriculture, also led to an increase in the availability of grain, in turn leading to an abundance of muscle power. Horses were the literal workhorses of industrial cities, grinding the pigments for dyes and paints, tobacco for snuff, charred bones for shoe polish, tannin-rich oak bark for leather, flint for glass and ceramics, and grain for flour, beer, and spirits. Horses fulled cloth, pounded rags into paper, flatted metal into sheets, and bored pipes, guns and even cannon. And of course they powered the transportation infrastructure, hauling the waggons and barges laden with goods.

A theme I keep coming across when I do my research is that there was a lot of effort put into what we might call the “improvement of animals”. I’ve touched on this briefly before, but I get a sense that there’s a whole lot of iceberg lying in wait under the surface for me to uncover. It likely extended to dogs, for example, who like horses were also often used for mechanical tasks. Just yesterday, for example, I read an account by a visitor to 1630s Bristol mentioning how the roasting spits at its inns were driven by dogs in treadwheels. At some point I need to go through all this evidence I’ve inadvertently collected.

FOUR. The Dutch Republic’s Golden Age did not fail because it lacked energy sources. I had already suspected this, as it never rang true, but had not quite appreciated the extent of the evidence: the fairly rapid collapse of so many Dutch industries in the 1650s-80s was, if anything, accompanied by a super-abundance of energy. Both peat and grain were in fact cheaper than ever, largely as a result of plummeting demand. Even the products made using wind —such as the timber sawn for ships along the windy banks of the Zaan river — failed to survive the general collapse in demand.

If energy had been lacking, we would have expected the prices of peat and grain to have been at all-time highs, not in a slump. Indeed, the lack of demand for peat and grain, by sapping demand for infrastructure projects like bog drainage and canal-building, is what led to the re-flooding of much of the Dutch countryside. The causes of the collapse are still something of a mystery to me, but I now feel very confident in ruling the energy theory out.

Those are my personal takeaways from the research, but there’s a whole lot more in the fuller piece, which you can read here. You can also read what Nesta’s Andrew Sissons has drawn from the piece in terms of lessons for energy policy today.

P.S. I managed to miss this newsletter’s fourth birthday, which was on the 5th October. I’m very grateful to you, dear readers, who have made it so worth researching and writing, and allowed me to continue it outside of a traditional university setting for so many years already. If you’re a new reader and would like to support my work, you can upgrade to a paid subscription here: