Engineering progress: Roma Agrawal on small inventions with big impacts

July 2023

Key Points

  • Roma Agrawal considers seven small inventions that changed the world in her book Nuts & Bolts
  • The engineer, who helped design The Shard, aims to spark people’s curiosity and engagement with the technology around them
  • She believes that making workplace culture more inclusive of minorities and women will result in better solutions

Author Roma Agrawal photographed by Antonio Olmos

Structural engineer Roma Agrawal arrives at the bank of the Thames, opposite the iconic Shard skyscraper, whose foundations and spire she helped design. The 72-storey building is the UK’s tallest. But Agrawal’s attention is fixed on a much smaller object that she removes from her handbag: a nail that she forged herself.

As she slides it between her fingers, she explains how little the object has changed since its invention 6,000 years ago. And, at the same time, how much it has changed the world.

“Nails cost almost nothing now, and they’re just rolling around in our drawers. But if I take you back some 400 years to Colonial America, nails were incredibly precious,” she says. “They were so expensive because Britain banned the export of nails to its colonies because it didn’t want the ones in the UK going anywhere else.”

The UK’s voracious appetite for nails – which artisans used in everything from constructing ships, to fastening roof boards to buildings, to fixing shoes to horses – ultimately led the US to develop its own nail industry.

American entrepreneurs built factories containing machines that could mass-produce nails at a rate of 100 units a minute by the early 1800s. Soon after, the US became a global competitor to the UK in the sector, teaching a valuable lesson about the risks of protectionism.


Early interest

Starting small to tell a bigger story is the central point of Agrawal's book, Nuts & Bolts: Seven Small Inventions that Changed the World. It charts the history of the nail, string, wheel, magnet, spring, lens and pump.

Agrawal’s fascination with engineering began when, as a curious child, she broke apart crayons and ballpoint pens to see how they worked. She spent her early years in India, where teachers give great weight to science, technology, engineering and mathematics (STEM) subjects. So it wasn’t odd that she was, in her own words, “a maths and physics nerd”.

She became aware that others perceived her passion for the subjects as unusual when she moved to the UK to study for her A-levels and later to take a Physics degree at Oxford University. And when she subsequently specialised in engineering, she gained a greater awareness of being in the minority – to this day, only 15 per cent of engineers in the UK are female, although the figure is higher in the Middle East and Asia.

Journalist Jane Wakefield talks to Roma in London

This prompts the question: what would she change to improve the balance? She answers without hesitation. “The culture of the workplace.”

“I would go on construction sites as a young engineer, and there would still be pictures of naked women on the walls. There was a narrative for a while that we, as minorities, needed to adapt to fit in. That we, as women or as people of colour, need to adapt to the workplace to thrive. Now we’re saying, hold on a second, why can’t the workplace culture be such that all our differences are embraced and that we can all thrive?”


Stone Age string

Writing Nuts & Bolts challenged Agrawal to question some of her own preconceptions as she delved into the origins of her selected inventions.

“String was probably the most surprising,” she says. “We don’t often think of string as being an engineering invention or a piece of innovation, but it has developed over hundreds of thousands of years from something we used to make clothes into something that now holds up bridges.”

By chance, archaeologists made a remarkable and unexpected discovery that string dates back to the Neanderthals while Agrawal was researching the subject.

“They only found evidence of this three years ago while I was writing my book,” she explains. “They found this tiny little piece of string in France that Neanderthals had created by twisting fibres from the bark of a tree.”

String’s Stone Age inventor remains unknown, but Agrawal uses her book to name and celebrate some of science and engineering’s other unsung heroes. From Stephanie Kwolek, who invented the bulletproof vest material Kevlar, to Josephine Cochran, who patented one of the first workable dishwashers back in 1886, to Indian scientist Jagadish Chandra Bose, a pioneer in wireless technology.

So would the world look very different if there had been more female engineers or those from more diverse backgrounds? Agrawal points out that many men had tried and failed before Josephine Cochran cracked the dishwasher.

“I always conjecture that is because men never wash dishes,” she laughs.

But on a more serious note, she is emphatic that all marginal communities need a voice in engineering. “Otherwise, you are not going to get the best solutions that work for everyone.”


Focusing on the lens

The most personal part of Agrawal’s book is the chapter on the lens, which begins with a letter to her daughter who was born via IVF. “I got to see you before you went into my body,” she writes. “You wouldn’t exist without a seemingly simple little curved piece of glass.”

She explains that the lens was part of a microscope that had let scientists create the embryo that became her child.

“Microscopes became a little bit of a fascination. And I basically tried to keep breaking all these complex pieces of technology down to the elements.

“By breaking things down, we can understand them better.”

And that is essentially the message of her book. By exploring the origins and impacts of seven small but critical inventions, we can better appreciate how they helped shape the world over centuries, sometimes millennia, and acknowledge the human endeavour involved.

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