Speaking of colours, as we were yesterday, I see that this year’s Limerick Literary Festival, which takes place later this month, will be opened by the Duchesse de Magenta.

The Duchesse de Magenta is better known to friends and family as Amélie de

Mac-Mahon. This may help explain why she will be appearing in Limerick. Via her late husband, she inherited the surname from a Clare-born ancestor who joined the flight of the Wild Geese after Sarsfield’s surrender in 1691.

As for the colourful title, that came from a more recent forebear, Patrice de

Mac-Mahon, an army general and, in the 1870s, President of France. By then, he was known among other things as the Duc de Magenta, because Magenta – a town near Milan – was the scene of one his greatest military victories, during the second Italian war of independence.

The family’s association with the colour, therefore, is only coincidental. It so happens that the magenta you might paint your bedroom walls with was first synthesised around the same time as the battle. So after a short period of being called fuschine – from fuschia – it acquired the name it has

now.

As a result, today, the colour is better known than the town, at least outside Italy. And well it might be, because it was at the forefront of a revolution that, with apologies to the second Italian war of independence, may have done more to change the world than any battle.

Magenta didn’t start this revolution, it’s true. As historian Norman Davies has written, that honour belongs to mauve, the world’s first synthetic dye: accidentally created in 1856 by a London chemist who had been trying to produce an anti-malarial drug instead.

Before then, all colours and pigments used in industry or the arts had to be extracted from natural materials. But where mauve led, as Davies explains in his book Europe: a History, a profusion of other artificial dyes followed, including magenta and violet imperial (1860), anilene yellow (1863), alizarin red (1871), and London orange (1875).

By the late 20th century, more than 4,000 synthetic dyes were being produced commercially, for use in everything from clothes and wallpaper to television and cinema. Together, they made the modern world so violently colourful that artists are now sometimes reduced to toning it down again (witness the Coen Brothers’ new movie), for aesthetic effect.

Mind you, artists tend to have more intense relationships with colour than most of us. And this doesn’t just apply to visual artists, either. Well known is the neurological phenomenon called synesthesia (or chromesthesia), in which, most typically, musical notes are perceived in colourful form.

The condition affected such composers as Liszt and Rimsky-Korsakov, while Alexander Scriabin went so far as to develop the idea into a formal spectrum. And I’m grateful to a number of readers who have pointed out that the Oscar-winning Disney song, Color of the Wind, mentioned yesterday, was also written by an acknowledged synesthete, Stephen Schwartz.

In a recent interview, Schwartz spoke of always experiencing his favourite key, D flat major, as “deep orange”. B major, by contrast, was “bright purple”, C major “yellow”, and so on. Mind you, he also admitted that there was no correlation between his colour scheme and Scriabin’s, suggesting that the perceptions were “highly subjective”, rather than conforming to any rules.

As for Scriabin and Rimsky-Korsakov, who compared notes on the issue, they were only in part agreement on specifics. They both considered D Major, for example, to be “golden brown”. But they differed sharply (no pun intended) on E flat major, with Scriabin seeing it as red/purple, and Rimsky-Korsakov blue.

Anyway, this may or may not lend credence to the concept, shared by the ancients and Flann O’Brien, that the winds have colour, differing according to their direction. Maybe, to fit with conventional models of synesthesia, the winds would have to be whistling.

But where was I? Oh yes, I was mentioning the Limerick Literary Festival, which used to be the Kate O’Brien Weekend, and still is, sort-of. In fact, the website address remains kateobrienweekend.com. It’s just that, like the River Shannon recently, the now 30-year-old weekend has burst its banks to take in a broader swathe of material.

The 2014 event begins on February 20th, with the aforementioned Duchesse de Magenta, and continues with an almost equally colourful line-up, including Anne Enright, Michael Longley, and Claire Tomalin. But of course no Irish literary festival would be complete without at least one O’Brien. So in the absence of Kate or Flann, the organisers are grateful for Edna, who will be the keynote speaker, in an interview with Mike Murphy.

fmcnally@irishtimes.com