Isabella Whitworth

probably more than natural and synthetic dyes, wax, resists, and history

Tag Archives: tannins


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A Scottish Post

I’m just home after a fortnight in Scotland, which started at the annual DHA (Dyes in History and Archaeology) conference at the University of Glasgow. I tend to know people by their research – and that’s how they know me. Someone at DHA greeted me as Mrs Orchil: she could also have hailed a Dr Indigo, a Ms Madder and Professor Purple. It’s a friendly conference attended by many world experts in the fields of dyes and pigments, but it welcomes independent scholars like me as well as dyers and textile makers.

I wasn’t giving a paper this year so it was an entirely stress-free conference and I sat back and enjoyed it, or at least, all the bits I understood. There are always some technical papers at DHA concerning dye analysis; the ones packed with acronyms, graphs and molecular structures streak comet-like above my head. But factual gems can lurk amongst figures and statistics, so it’s worth not totally tuning out.

I took a small ‘suitcase’ exhibition with me about orchil and my research studies; most delegates came to look at it and talk to me, and as a result I learned new things about orchil from new perspectives.

The conference tour, after two packed days of papers, took us to Glengoyne Distillery for a fortifying wee dram preceding a tour of the plant, and thence to Stirling Castle where we visited the Tapestry Studios to see the final piece in the Unicorn Series nearing completion.

Sherry and tannins

The Glengoyne tour outlined the lengthy procedure for ageing whisky in casks. Casks are made from different types of oak, but have once held sherry (and some, if I remember correctly, Bourbon). The ageing whisky gradually absorbs colour and flavour from the sherry, and the tannins in the oak cask. The two images above illustrate ageing over thirty years in two different types of cask, with coloration intensifying every year. Evaporation is also evident, with around half the liquid being lost over the period. This lost alcohol is called ‘The Angels’ Share’.

Textile Tweets

Lobaria pulmonaria, or lungwort. This lichen is endangered and should not be used for dyeing
Workers’ cottages at Alexandria, Levenside, near old Turkey Red works
Explanation of ‘crotal’ from Dwelly’s Gaelic dictionary. Note the old name for lungwort ‘Stricta pulmonacea’
The Plaiden Ell at Dornoch. Two metal pegs set apart in the slab created the standard measurement for cloth
Ochrolechia tartarea, or the cudbear lichen, on the banks of Loch Ewe
Visit to Stirling Castle on DHA tour to see the last of the Unicorn tapestry series being woven
Explanation of ‘corcur’ from Dwelly’s Gaelic Dictionary

About the pictures

Above is a small selection of textile-related images from Scotland, most of which I tweeted during our trip. My obsession with dye lichens was rewarded by finding Ochrolechia tartarea alongside Loch Ewe, and Lobaria pulmonaria  at Oban; Parmelia saxatilis and P. omphalodes were growing at many locations.  Note: I was looking, not collecting. A Gaelic-English Dictionary in a hotel room confirmed that in Gaelic crotal refers to boiling water method lichens, but corcur to orchil lichens. If you want to know what orchil is, or read more about my research and views on dyeing with lichens, please visit this page.

Turkey Red

I spent a week with Deb Bamford (aka The Mulberry Dyer) learning how to dye Turkey Red at a Summer School in 2013. Read about it from this blog post forwards. In Scotland I found remnants of the Turkey Red industry buildings at Alexandria, on Levenside. There is a great website about the Turkey Red industry here. And read this wonderful book:

Colouring the Nation: The Turkey Red Printed Cotton Industry in Scotland c1840-1940 by Stana Nenadic and Sally Tuckett. Published by National Museums Scotland. From Amazon here.

Unicorn Series: Stirling Castle and West Dean Tapestries

For more on the Unicorn Series, go here for the Stirling Castle story, and here for West Dean’s version.

 Glengoyne Distillery, Dumgoyne Glengoyne Distillery


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Follow-up on gall ink

Gall ink

Just before Christmas I wrote about my experiment making ink from oak galls. Read it here. I tried using the mixture as an ink fairly early on in the experiment, using recipes found on the internet, with disappointing results. It came out very pale and did not darken with exposure to light as I had read that it would. That could be for many reasons.  I maybe didn’t use enough galls, or fresh ones, or I hadn’t left it all to soak enough; maybe the mixture was insufficiently concentrated; maybe I hadn’t added enough iron. I also learned that ink would flow better with the addition of gum arabic. I couldn’t find my stock of gum arabic, so I sent off for some (in powder form).

Galls still soaking
Ink, round one, without gum arabic
Gall ink with gum arabic
Ink, round two, concentrated, and with addition of gum arabic

When the gum arabic arrived I decanted some of the gall liquid, added an iron mixture (made from rusty nails and vinegar) and allowed it to reduce naturally by leaving the jar in a warm dry place. I hoped to concentrate the pigment. I then added a small quantity of powdered gum arabic and made some drawings and scribbles using sharpened twigs: a proper quill pen would have been great, but I was short of a goose.  The second ink result was somewhat better than the first, but having looked at some manuscripts written in gall ink, I think it could be a more intense brown/black. I’m leaving the galls to continue soaking and will try again later in the year – as well as looking for more samples in late summer when they will be fresh.

Time will tell if I have used too much iron and my ink rots through the paper – definitely a problem with ‘over-ironed’ dyes of the past which ate their way through wools and silk.

I spent my childhood in the New Forest and have enjoyed following artist Stephen Turner’s blog about his year in the ‘Exbury Egg’. I know the area he is writing about intimately. Coincidentally, Stephen has undertaken a similar experiment with gall ink and you might like to look at two of his posts. He describes collecting galls here, and his ink results here. Stephen’s observations on the Turkey oak (Quercus cerris) were completely new to me: apparently this species was reintroduced into the British Isles in the eighteenth century and there were concerns that acorn production, vital for the local feeding of pigs, was affected by the arrival of the Turkey oak and its attendant galls. The Oak Marble Gall Wasp (Andricus kollari), for which a Turkey oak is vital, is responsible for the marble galls Stephen used.

The galls I collected in Devon are not the same thing as Stephen’s New Forest marble galls. They were found on a different type of oak and produced by a different wasp. But as far as I know all galls are tannin-rich and can be used to produce ink. So I’ll keep try-ink. Sorry, couldn’t resist that one.

 

Breaking news.. extra course at West Dean: Brilliant with Pattern

Because my West Dean course in March has a waiting list double the size of the course itself, the organisers have scheduled an extra course from 9th – 11th  May. See the West Dean programme here. You can also download the full West Dean College Course programme here.


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Gall-ink…

Last week I found some oak-galls, or oak apples, in a hedge. They were easy to spot after the final fall of leaves. Oak galls are nothing to do with acorns. They result from  chemicals injected into a developing leaf bud when a female gall wasp lays eggs.

photo 4

Oak galls spotted in a hedge

The galls contain high proportions of tannin and, mixed with iron salts, were historically the source of a purple-black or brown ink. The comprehensive and scholarly Iron Gall Ink Website has an ink history here. The fourth century  Codex Sinaiticus, one of the most complete versions of the Bible, was written in iron gall ink, in Greek. Follow the link to read about a great collaborative project, and an entire website devoted to the Codex. Because the manuscript has been broken up and spread worldwide, the project exists to reunite it digitally. 

Anyway, I picked the galls and am soaking them out. Apparently I can use a solution of rusty nails to make up the ink, according to Wikipedia’s recipe, and I shall try it in the New Year when I have found my Gum Arabic.

All this think-ink reminded me of an encounter with shaggy ink caps (Coprinus comatus) a few Novembers back. I found an ink-cap-ink recipe – and the delightful word deliquesce – on Regia Anglorum’s site here, recipe number 3. No cauldrons were available that week, so a plastic pot emptied of E numbers sufficed for deliquescing. The fungi did their thing and weren’t particularly smelly at first. They just looked a bit sinister (shaggy ink caps aren’t poisonous, although I wasn’t planning an omelette). I put the increasingly soggy black mixture in the corner of my studio and forgot about it. Until it began to make its presence felt. 

It produced a putrid, mouldy, rotting smell which was murderously  incriminating. I poured the mixture through a sieve at arm’s length and improvised a cooking put from an empty tin. If the smell was bad before, nothing compared to the hellish fumes that arose from the pot once on a stove (some recipes suggest that boiling reduces and blackens the mixture). The mixture obediently reduced to a ghastly, shiny black mucus. The stench was so bad I had to hold my breath to stop myself gagging. To hell with research like this – I couldn’t live with the smell. I poured off the mixture and found a large paintbrush and some paper and made a simple snot drawing (see below). I then introduced the mixture to the far corner of the garden.

The conclusions the Ink Cap Escapade were:

1.That the recipes I found are incomplete, or some additional ingredient neutralised the decomposition and the smell. Vinegar, perhaps? As the fungus is only found in autumn, there must have been a way to preserve the ink through the year without knocking out an entire community of Cistercians with the pong. Or maybe I’ve stumbled across a new cause of the Reformation.

2. A lot of ink caps would be needed to make a good black and you couldn’t use a quill with the snot-like stuff I made. It needs to be blacker and more runny. It was too thick for a small paintbrush. Maybe I boiled it too hard.

3. Perhaps monks had no sense of smell.