By Jo Barstow, British Science Association Media Fellow


This year’s British Science Festival was heralded by an urgent call from incoming BSA President Professor Dame Athene Donald to bridge the divide between science and arts in the UK.

I was delighted to be interviewing PhD student Julie Wertz, who is doing exactly that. Julie is the winner of the inaugural Jacob Bronowski Award Lecture for science and the arts, and she’s using her knowledge of chemistry to unravel the mystery of textile dyeing in 19th century Glasgow.

Hailing from Nebraska, Julie studied Chemistry and French at the University of Nebraska-Lincoln. After a brief stint in pharmaceutical quality control she moved to the University of Glasgow, where she holds a prestigious Lord Kelvin Adam Smith scholarship. Her PhD project, studying the historical process that created the durable but complex dye Turkey Red, has enabled her to combine her love of chemistry, textiles and French. Julie chatted to me after her lecture, in which she explained her attempts to recreate the dyeing process using instructions provided in historical sources.

You said in your lecture that your love of textiles goes back to your childhood, but what got you interested in chemistry?
My parents got me a chemistry set because I did really well on my kindergarten report card. I thought it was really cool the way you could make things happen. As I got older, I found that chemistry was a really good way to explain things that were happening around me.

You are trying to recreate the process for making Turkey Red, a dye manufactured in Glasgow in the 19th century. Why was it so important?
It’s very light-fast, it’s very wash-fast, it’s fast to bleaching as well. They used to use it in the Irish linen industry to embroider and mark cloth, because even if you washed and bleached your linen the Turkey Red would still stay red. 

Why do you think it’s so important to understand how Turkey Red was made, now that it’s no longer used? Do people ever ask why you aren’t developing new chemicals that might be useful in the future?
I think in a world of limited resources, it’s important to look at the processes that we’re using. I’ve had people say to me, 'I wouldn’t touch [synthetic dyes], I only use natural dyes' – but natural dyes are chemicals too. Natural dyes can be a big environmental resource drain. When people question my research I like to give them a way to consider how it fits into wider context.

So natural isn’t always better. In fact, isn’t the Turkey Red process dangerous? You also said in your lecture that the cotton fibres need to be coated first with a special oil – is the oil dangerous to make?
One of the questions I was asked during the [PhD] interview was, “Do you have any objections to working with animal dung?” The old process for Turkey red used it, and they also used cattle blood. In the oil making there’s sulphuric acid and strong caustic bases, and I had to work with anthracene, which is a carcinogen.

Those dangerous chemicals contribute towards making some extremely beautiful textiles, and it’s clear that you appreciate that side of your research. Do you find visual beauty an important tool for communicating science to the public?
I think if I were studying brown textiles it wouldn’t be nearly as exciting. A lot of the language of science can be fairly intimidating, but something that is visually appealing is a way for everybody to connect to it.

You must be getting close to the end of your PhD now, so what do you see as the conclusion of your research?
I’d like to put a 21st century recipe out there, a series of processes that other people can use. I think it would be really interesting if they can explore making Turkey Red, either as an artisanal industry or as an actual product.

Did you have a ‘Eureka!’ moment during your PhD?
The oil [that coats the cotton fibres before the dye is applied] was one of those questions… nobody could figure it out. [Other people] looked at it the way that everyone else studies dyes, which is to extract them [from the fabric]. But no other dye requires so much preparation of the fibre before. I thought, “The way we’re looking at it isn’t right,” but looking at it on the fibre is difficult.

You said in your lecture that you used a technique called Diffuse Reflectance Infrared Spectroscopy  - basically shining infrared light onto the fabric and measuring the reflected light that comes back – to look at the dye without extracting it from the cotton fibre. What happened when you did that?
John Liggat at the University of Strathclyde referred me to a technician at [chemical analysis company] Agilent. The technician let me try out his instrument on some samples, and I saw something. He said “You shouldn’t see something!” and then I did… and for about six months after that I genuinely thought,  “Somebody’s going to prove me wrong!” But that’s when it all started to come together, when I was able to say something about the oil.

You obviously love working in a field that crosses the science-arts divide. Was it easy for you to pursue both interests growing up, or were there challenges?
[In the USA] we don’t choose subjects in high school at all, you just graduate with a general diploma. I’d chosen French because I always liked the way it sounded. I chose chemistry because I was originally interested in the textile science programme my university offered, but the emphasis was more toward fashion design and marketing than actual fabrics and fibres and history. I spent four years defending my choice to anybody I talked to. But you know what? I’m reading manuscripts in French now, and performing chemistry, so I think people should be allowed to study whatever they want.

Dr Jo Barstow is a 2015 British Science Association Media Fellow. Her Fellowship was funded by STFC, and she was placed at the Conversation. She is a post-doctoral researcher in Planetary Physics at the University of Oxford.