When an Indian man invented a simple machine for poor rural women to make cheap sanitary pads, the idea was to provide jobs for some, and hygiene for millions - often for the first time. The story gave one British woman an idea that quickly became her mission in life.
Amy Peake is experimenting in her kitchen in a remote corner of south-west England, ripping apart different kinds of sanitary pads and testing their absorbency. She has just returned from another fact-finding trip to India, where these pads were made.
Her family tolerate her eccentric behaviour without completely understanding it - her six-year-old daughter calls it "the knicker thing".
"I didn't expect to become an expert in sanitary pads, but I probably know as much as anyone else in the world about these low-cost pads now," Peake says, laughing at the unexpected direction her life has taken.
Her obsession began one morning in March 2014 when she went to the doctor for a routine appointment.
Leafing through a magazine in the waiting room, she saw an image that shocked her. It showed thousands of refugees queuing for food in a bombed-out street in Damascus. In the foreground stood a woman, and for a split second she thought, "What if I was her? What if my children were there? And what if I got my period?"
Then a remarkable coincidence occurred.
When she got home, her husband showed her a BBC News Magazine story about Arunachalam Muruganantham, an Indian man who had invented a machine to produce cheap and hygienic sanitary pads after realising his wife, and millions of other Indian women, used rags. Muruganantham didn't want to sell the pads, he wanted women to make and sell their own - his aim was to create a million jobs for poor rural women in India, and he planned to expand to other countries where sanitary pads are unavailable.
Peake immediately thought: "That machine should be in the refugee camps - and if it isn't, perhaps I should take it there."
She experienced a kind of revelation.
"It was one of those scary moments where that purpose that you have been looking for all your life is staring you right in the face," she says.
Peake began to drum up interest for the project, which she idealistically called Loving Humanity. But who would listen to a yoga teacher with no experience in business or charity?
One man laughed in her face - he thought she was crazy. And none of the big humanitarian agencies returned her calls.
But Peake is nothing if not tenacious, and after six months of this she decided to just go for it.
First, she decided to seek some official backing from a charity - maybe this would help her get taken seriously? Step up the St Austell Rotary Club. This group of gents, average age 70, were not entirely comfortable discussing periods - "I made the chairman blush just by shaking his hand," says Peake - but they gave her their blessing.
Next, she collected 40kg of donated baby clothes and jumped on a plane to Jordan - host to more than a million Syrian refugees - to meet local volunteers. With their help, she finally made it to the country's largest refugee camp, Zaatari.
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This vast desert camp houses 79,000 Syrians in container homes, most from the town of Deraa, just over the border - some say they can see the city's lights twinkling across the desert night. Once inside, Peake discovered that the problem was far greater than she had imagined.
About one in four of Zaatari's residents need sanitary pads. The UN does distribute them now and again to women aged 14 to 45, but there are never enough to go round.
On top of that, Peake discovered, there is a desperate need for incontinence pads for the many wounded, elderly and disabled people - and traumatised children. "The children are really suffering," says Peake. "The problem is that the mothers have been trying to cope for so long that basically they've given up. Night after night of urine and they can't keep them clean. It's soul-destroying."
The camp authorities expressed a cautious interest in her idea, but it was up to her to make it work. "I thought I would be able to hand this over to an organisation but they are all so busy they can't take anything else on," said Peake. "I'll have to give birth to it myself." That was November 2014.
A few weeks later she was on her way to Coimbatore, in southern India, to meet Muruganantham. She met a man who was passionate about changing women's lives, but set in his ways. Despite his worldwide fame he hadn't taken on any staff, and still lived in a modest rented apartment.
Learning how to use his equipment, a series of simple machines, took her less than 15 minutes. First, compressed wood pulp goes into a grinder - the resulting fluffy material is shaped in a mould, then wrapped in anti-bacterial fabric and placed under a UV light for 30 seconds to be disinfected.
It really was that simple, and Peake could already picture her factory in Zaatari.
But there was a problem.
Muruganantham's price for providing the raw materials was too high. Shipping them from India to Jordan would cost her $5,000 (£3,300) every four months - too much for the project to be self-sustaining.
Furthermore, Peake's attempts to source materials more cheaply were thwarted, because she couldn't find out exactly what she needed.
Muruganantham would not tell her, and nor would the sanitary pad companies.
"I've been talking to manufacturers since the beginning of the year but it's like trying to get information out of the mafia. It's like hitting my head against a brick wall," she said in June.
It began to look as though her dream was not feasible, and the money she had raised - about $22,000 (£14,500) - would be best spent buying a container of sanitary towels as a one-off donation.
"It's so sad, it's the best invention in the world - it's a tragedy if it doesn't work," she said.
The Indian connection
Muruganantham was a school dropout from a poor family in southern India. In 1998 he saw his wife was hiding something from him and was shocked to discover what it was - rags, "nasty cloths" which she used during menstruation. She told him sanitary pads were too expensive, so he set about inventing a simple machine to make them cheaply. It was a long process - he nearly lost his family, his money and his place in society.
But Muruganantham, despite his secrecy regarding the raw materials, has been generous in allowing others to copy his machine.
"I am allowing them to do it - no problem, it's not a business, not a patent," he says.
So nearly a year after her first trip, Peake went back to India to find a new partner - and her first visit was to a person who has used a modified version of Muruganantham's technology to bring feminine hygiene to Vadodara, a town in the western Indian state of Gujarat.
Swati Bedekar used to be a teacher trainer until she realised how many girls dropped out of school when they started to menstruate - in rural India many women still use unhygienic materials, and some are even made to sit on a pot of sand during their period. Bedekar bought Muruganantham's machines in 2010, and now hundreds of women in Vadodara earn a living from making sanitary pads.
Bedekar's husband Shyam has made elements of the machine smaller and quieter, and their pads look quite different. Excitingly, for Peake, they have wings to secure them - a feature Muruganantham regards as an unnecessary complication. What's more, the machines can also produce incontinence pads. Most importantly, shipping the raw materials would be affordable.
That's not to say it was all plain sailing - when she first arrived, Peake found to her horror that the Bedekar's innovative sealing method made the pads quite noisy - "I sounded like a wastepaper basket walking across the floor" - but they experimented, and together they came up with a solution.
She felt she had found her ideal partners - but she had another visit to make.
Afzal Shaikh is based in Mumbai and imported the raw material used to make sanitary pads for years before going into production himself. His materials are even cheaper than the Bedekars' and Peake also liked one of his machines, which is particularly efficient at producing fluffy wood pulp for the larger incontinence pads.
With these two new potential partners, Peake's project was back on track, and in overcoming her setbacks she had learned valuable lessons.
"I feel like I'm ready," says Peake at the end of her second India trip. "If I had succeeded the first time, I wouldn't have all the understanding I have now."
Last month, armed with a suitcase full of low-cost sanitary and incontinence pads from India, she went back to spend a week in Zaatari.
Would the women use her products? And would they be willing to make them?
Coming up to their fifth winter in the camp, most of the refugees have spent whatever money they came with, and the situation is getting desperate. There is a brisk trade in UN food vouchers - refugees receive 20 Jordanian dinars ($28; £20) per month. Some swap them for milk or food, which they then sell. They lose money on the deal, but with the cash they can buy what they need from the 3,000 market stalls that have sprung up in Zaatari. There are even kiosks that sell only sanitary products, but prices are very high.
A group of five teenage girls have gathered in a community centre in District 10, waiting to discuss this most sensitive of topics. A 17-year-old girl says that two months after a UN distribution, the pads have usually run out. She is too embarrassed to ask her father to buy them for her, so she goes to the market by herself. Her mother is above the age at which she is eligible for free sanitary pads from the UN, so she uses rags, as do many of her neighbours.
Peake asks if the washed rags are ever hung out to dry - the teenagers respond with a horrified "No!" This need for discretion, together with a shortage of detergent, means they can't be properly cleaned.
One 13-year-old giggles throughout the discussion, but then is eager to share her big secret - she, too, has had her first period. It happened at school. "I went to the teacher and told her what happened and she explained that it's physical changes and it's normal for a girl," she says.
She hasn't told her mother yet - perhaps because once a girl has had a period she's considered an adult, and no longer allowed to play outside.
"Most of our young girls at this age are dreaming to have their period, so they can get married after one year," says Wijdan, the translator. "We suffer from early marriage in this community. It's a very conservative community and they link girls with honour - they think, 'If I allow my daughter to get married early I protect her.'"
Peake is thinking of using women's centres to distribute pads, so that young girls like these can get what they need discreetly. With her ready smile, she is in her element meeting people in the camp. Not everyone is enthusiastic, though - some of the older women grumpily tell her they would rather have heaters than sanitary pads.
What is clear is how desperately people need incontinence pads. "I had a woman with four incontinent children asking me, in tears, 'Please can you be quick because the winter's coming and it's so difficult to keep everybody warm and dry,'" she says.
In the darkness of a dust storm Peake visits perhaps the oldest man in Zaatari - born in 1913, Yousef arrived in the camp two years ago. He has recently been given a bed, but spent the previous two years lying on the floor. The former farmer has 51 grand- and great-grandchildren and is looked after by his daughter, a widow.
His daughter turns to Peake with tears in her eyes, begging for help. Adult nappies cost 5 dinars ($7; £5) for a pack of 12, a quarter of her monthly income. When she has no nappies she improvises with rags and plastic sheeting - she pulls back the blanket to show what makeshift arrangements are in place. Despite this, she says he has no bedsores. "I wash him every day. He is my father," she says.
"She could spend all of her money buying nappies and not have enough money at all for food, so this is why it is such a compromising situation for everybody," says Peake.
But the most emotional visit is yet to come.
Nazleh and her husband live in a metal container home with their six children, aged 10 to 21. The four eldest have a degenerative muscle wasting condition and are unable to walk. Their 17-year-old daughter Elham spends her days on social media - she is able to control her phone, but her hands are not strong enough to do much else. Her condition began to affect her when she was nine - she began to walk more slowly, then could not walk at all.
"We were so happy before the crisis in Syria," says Nazleh. They worked as farmers and were able to look after their children, but when the war started they lost their home.
It took the family two months to travel from Deraa to the Jordanian border because they had no car. Nor did they have wheelchairs. They had to carry the children on their backs.
There is no bathroom in their container, so when she can't find money for nappies Nazleh has to carry her four children to the communal toilets. Her husband earns some money by cleaning these toilets once every four months, but the rest of the time they sell food vouchers to get cash. She spends 50 dinars ($70; £50) on nappies a week and now owes the nearest stall-holder 200 dinars ($280; £200) - a debt that is likely to increase.
"Today was very difficult," says Peake afterwards. "I didn't realise the scale and the impact potentially of what I'm doing.
"This woman is selling everything she has to look after her children. Where you have mothers with more than one daughter who has periods, or lots of disabled children, the problem becomes insurmountable very quickly."
Finally, she gets the news she has been waiting for. The UNHCR camp manager, Hovig Etyemezian, agrees to host a six-month pilot. He wants to start small before scaling it up. "We want to try it out," he says. "Producing such items in the camp by residents is much better than distributing them."
The workers will earn a salary, but there is still a lot to work out, like how the pads will be distributed and how much to charge - or whether to charge at all.
But if it works in Zaatari, it could work anywhere. "Whenever there's a success story it's easy to replicate. The difficulty is to have a success story," Etyemezian says.
It is an ambition Peake shares.
"My vision is that this machine goes all over the world to help poor underprivileged women financially by allowing them to work," she says.
The process has begun in India, and thanks to an unstoppable woman in Cornwall, it will now be tested in Zaatari. How much further can it go?
"This is actually so much more than periods," says Peake. "This is so big for women."